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<h3 style="margin-top: 20px; margin-bottom: 10px;">
Marge Bot pushed to branch wip/marge_bot_batch_merge_job at <a href="https://gitlab.haskell.org/ghc/ghc" style="color: #1068bf;">Glasgow Haskell Compiler / GHC</a>
</h3>
<h4 style="margin-top: 10px; margin-bottom: 10px;">
Commits:
</h4>
<ul>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/8281bc021090523218e44b3df3d558921e581cad" style="color: #1068bf;">8281bc02</a></strong>
<div>
<span> by Bodigrim </span> <i> at 2022-11-20T10:49:02-05:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: #fafafa; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dbdbdb;'>Extend documentation for Data.IORef
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/d720c28826afa162c44fea058d15eadeddb877e1" style="color: #1068bf;">d720c288</a></strong>
<div>
<span> by Simon Peyton Jones </span> <i> at 2022-11-20T10:49:03-05:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: #fafafa; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dbdbdb;'>Buglet in GHC.Tc.Module.checkBootTyCon

This lurking bug used the wrong function to compare two
types in GHC.Tc.Module.checkBootTyCon

It's hard to trigger the bug, which only came up during
!9343, so there's no regression test in this MR.
</pre>
</li>
</ul>
<h4 style="margin-top: 10px; margin-bottom: 10px;">
3 changed files:
</h4>
<ul>
<li class="file-stats">
<a href="#e65390fa5a32c453a81a1c9a3e1c4464d155ca4a" style="color: #1068bf;">
compiler/GHC/Tc/Module.hs
</a>
</li>
<li class="file-stats">
<a href="#92fe5f22b3fdb223e366dda9a11166bc66f8d35c" style="color: #1068bf;">
libraries/base/Data/IORef.hs
</a>
</li>
<li class="file-stats">
<a href="#35f0eb539f3f2c545653c8f00151a0d06945215f" style="color: #1068bf;">
libraries/base/GHC/IORef.hs
</a>
</li>
</ul>
<h4 style="margin-top: 10px; margin-bottom: 10px;">
Changes:
</h4>
<li id="e65390fa5a32c453a81a1c9a3e1c4464d155ca4a">
<a href="https://gitlab.haskell.org/ghc/ghc/-/compare/2d4b06ebd34427f711dda87a3b60ba69e5637243...d720c28826afa162c44fea058d15eadeddb877e1#e65390fa5a32c453a81a1c9a3e1c4464d155ca4a" style="color: #1068bf;"><strong style="font-weight: bold;">compiler/GHC/Tc/Module.hs</strong></a>
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<table class="code white" style="border-spacing: 0; border-collapse: collapse; width: auto; font-family: monospace; font-size: 90%;" bgcolor="#fff" width="100%" cellpadding="0" cellspacing="0">
<tr class="line_holder match" style="line-height: 1.6;">
<td class="diff-line-num unfold js-unfold old_line" data-linenumber="1096" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="diff-line-num unfold js-unfold new_line" data-linenumber="1096" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -1096,6 +1096,7 @@ checkBootTyCon is_boot tc1 tc2</td>
</tr>
<tr class="line_holder" style="line-height: 1.6;">
<td class="old_line diff-line-num" data-linenumber="1096" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1096
</td>
<td class="new_line diff-line-num" data-linenumber="1096" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1096
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1096" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">-- Order of pattern matching matters.</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1097" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1097
</td>
<td class="new_line diff-line-num" data-linenumber="1097" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1097
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1097" class="line" lang="haskell">       <span class="n" style="color: #333;">subDM</span> <span class="kr" style="font-weight: 600;">_</span> <span class="kt" style="color: #458; font-weight: 600;">Nothing</span> <span class="kr" style="font-weight: 600;">_</span> <span class="o" style="font-weight: 600;">=</span> <span class="kt" style="color: #458; font-weight: 600;">True</span></span>
</pre></td>
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<tr class="line_holder" style="line-height: 1.6;">
<td class="old_line diff-line-num" data-linenumber="1098" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1098
</td>
<td class="new_line diff-line-num" data-linenumber="1098" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1098
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1098" class="line" lang="haskell">       <span class="n" style="color: #333;">subDM</span> <span class="kr" style="font-weight: 600;">_</span> <span class="kr" style="font-weight: 600;">_</span> <span class="kt" style="color: #458; font-weight: 600;">Nothing</span> <span class="o" style="font-weight: 600;">=</span> <span class="kt" style="color: #458; font-weight: 600;">False</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="1099" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="1099" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
1099
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC1099" class="line" lang="haskell"></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1099" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1099
</td>
<td class="new_line diff-line-num" data-linenumber="1100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1100
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1100" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">-- If the hsig wrote:</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1100
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<td class="new_line diff-line-num" data-linenumber="1101" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1101
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1101" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">--</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1101" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1101
</td>
<td class="new_line diff-line-num" data-linenumber="1102" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1102
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1102" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">--   f :: a -> a</span></span>
</pre></td>
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<td class="diff-line-num unfold js-unfold old_line" data-linenumber="1103" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="diff-line-num unfold js-unfold new_line" data-linenumber="1104" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -1103,11 +1104,14 @@ checkBootTyCon is_boot tc1 tc2</td>
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<td class="old_line diff-line-num" data-linenumber="1103" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1103
</td>
<td class="new_line diff-line-num" data-linenumber="1104" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1104
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1104" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">--</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1104" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1104
</td>
<td class="new_line diff-line-num" data-linenumber="1105" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1105
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1105" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">-- this should be validly implementable using an old-fashioned</span></span>
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<td class="old_line diff-line-num" data-linenumber="1105" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1105
</td>
<td class="new_line diff-line-num" data-linenumber="1106" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1106
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1106" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">-- vanilla default method.</span></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="1106" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
1106
</td>
<td class="new_line diff-line-num old" data-linenumber="1107" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC1106" class="line" lang="haskell">       <span class="n" style="color: #333;">subDM</span> <span class="n" style="color: #333;">t1</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">GenericDM</span> <span class="n" style="color: #333;">t2</span><span class="p">))</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">VanillaDM</span><span class="p">))</span></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="1107" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
1107
</td>
<td class="new_line diff-line-num old" data-linenumber="1107" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC1107" class="line" lang="haskell">        <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">eqTypeX</span> <span class="n" style="color: #333;">env</span> <span class="n" style="color: #333;">t1</span> <span class="n" style="color: #333;">t2</span></span>
</pre></td>
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<tr class="line_holder new" style="line-height: 1.6;">
<td class="old_line diff-line-num new" data-linenumber="1108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="1107" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
1107
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC1107" class="line" lang="haskell">       <span class="n" style="color: #333;">subDM</span> <span class="n" style="color: #333;">t1</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">GenericDM</span> <span class="n" style="color: #333;">gdm_t1</span><span class="p">))</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">VanillaDM</span><span class="p">))</span></span>
</pre></td>
</tr>
<tr class="line_holder new" style="line-height: 1.6;">
<td class="old_line diff-line-num new" data-linenumber="1108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="1108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
1108
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC1108" class="line" lang="haskell">        <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">eqType</span> <span class="n" style="color: #333;">t1</span> <span class="n" style="color: #333;">gdm_t1</span>   <span class="c1" style="color: #998; font-style: italic;">-- Take care (#22476).  Both t1 and gdm_t1 come</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="1108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="1109" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
1109
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC1109" class="line" lang="haskell">                             <span class="c1" style="color: #998; font-style: italic;">-- from tc1, so use eqType, and /not/ eqTypeX</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="1108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="1110" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
1110
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC1110" class="line" lang="haskell"></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1108
</td>
<td class="new_line diff-line-num" data-linenumber="1111" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1111
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1111" class="line" lang="haskell">       <span class="c1" style="color: #998; font-style: italic;">-- This case can occur when merging signatures</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1109" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1109
</td>
<td class="new_line diff-line-num" data-linenumber="1112" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1112
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1112" class="line" lang="haskell">       <span class="n" style="color: #333;">subDM</span> <span class="n" style="color: #333;">t1</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">VanillaDM</span><span class="p">))</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">GenericDM</span> <span class="n" style="color: #333;">t2</span><span class="p">))</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1110" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1110
</td>
<td class="new_line diff-line-num" data-linenumber="1113" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1113
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1113" class="line" lang="haskell">        <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">eqTypeX</span> <span class="n" style="color: #333;">env</span> <span class="n" style="color: #333;">t1</span> <span class="n" style="color: #333;">t2</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="1111" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="1114" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
1114
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC1114" class="line" lang="haskell"></span>
</pre></td>
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<tr class="line_holder" style="line-height: 1.6;">
<td class="old_line diff-line-num" data-linenumber="1111" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1111
</td>
<td class="new_line diff-line-num" data-linenumber="1115" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1115
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1115" class="line" lang="haskell">       <span class="n" style="color: #333;">subDM</span> <span class="kr" style="font-weight: 600;">_</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">VanillaDM</span><span class="p">))</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">VanillaDM</span><span class="p">))</span> <span class="o" style="font-weight: 600;">=</span> <span class="kt" style="color: #458; font-weight: 600;">True</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1112" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1112
</td>
<td class="new_line diff-line-num" data-linenumber="1116" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1116
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1116" class="line" lang="haskell">       <span class="n" style="color: #333;">subDM</span> <span class="kr" style="font-weight: 600;">_</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">GenericDM</span> <span class="n" style="color: #333;">t1</span><span class="p">))</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">Just</span> <span class="p">(</span><span class="kr" style="font-weight: 600;">_</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">GenericDM</span> <span class="n" style="color: #333;">t2</span><span class="p">))</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="1113" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
1113
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC1117" class="line" lang="haskell">        <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">eqTypeX</span> <span class="n" style="color: #333;">env</span> <span class="n" style="color: #333;">t1</span> <span class="n" style="color: #333;">t2</span></span>
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</li>
<li id="92fe5f22b3fdb223e366dda9a11166bc66f8d35c">
<a href="https://gitlab.haskell.org/ghc/ghc/-/compare/2d4b06ebd34427f711dda87a3b60ba69e5637243...d720c28826afa162c44fea058d15eadeddb877e1#92fe5f22b3fdb223e366dda9a11166bc66f8d35c" style="color: #1068bf;"><strong style="font-weight: bold;">libraries/base/Data/IORef.hs</strong></a>
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<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -46,7 +46,9 @@ mkWeakIORef :: IORef a -> IO () -> IO (Weak (IORef a))</td>
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<td class="new_line diff-line-num" data-linenumber="46" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC46" class="line" lang="haskell"><span class="n" style="color: #333;">mkWeakIORef</span> <span class="n" style="color: #333;">r</span><span class="o" style="font-weight: 600;">@</span><span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">STRef</span> <span class="n" style="color: #333;">r</span><span class="o" style="font-weight: 600;">#</span><span class="p">))</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="n" style="color: #333;">finalizer</span><span class="p">)</span> <span class="o" style="font-weight: 600;">=</span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="o" style="font-weight: 600;">$</span> <span class="nf" style="color: #900; font-weight: 600;">\</span><span class="n" style="color: #333;">s</span> <span class="o" style="font-weight: 600;">-></span></span>
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47
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<td class="new_line diff-line-num" data-linenumber="47" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
47
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC47" class="line" lang="haskell">    <span class="kr" style="font-weight: 600;">case</span> <span class="n" style="color: #333;">mkWeak</span><span class="o" style="font-weight: 600;">#</span> <span class="n" style="color: #333;">r</span><span class="o" style="font-weight: 600;">#</span> <span class="n" style="color: #333;">r</span> <span class="n" style="color: #333;">finalizer</span> <span class="n" style="color: #333;">s</span> <span class="kr" style="font-weight: 600;">of</span> <span class="p">(</span><span class="o" style="font-weight: 600;">#</span> <span class="n" style="color: #333;">s1</span><span class="p">,</span> <span class="n" style="color: #333;">w</span> <span class="o" style="font-weight: 600;">#</span><span class="p">)</span> <span class="o" style="font-weight: 600;">-></span> <span class="p">(</span><span class="o" style="font-weight: 600;">#</span> <span class="n" style="color: #333;">s1</span><span class="p">,</span> <span class="kt" style="color: #458; font-weight: 600;">Weak</span> <span class="n" style="color: #333;">w</span> <span class="o" style="font-weight: 600;">#</span><span class="p">)</span></span>
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48
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<td class="new_line diff-line-num" data-linenumber="48" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
48
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC48" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num old" data-linenumber="49" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
49
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<td class="new_line diff-line-num old" data-linenumber="49" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC49" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Mutate the contents of an 'IORef'.</span></span>
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<td class="old_line diff-line-num new" data-linenumber="50" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="49" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
49
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC49" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Mutate the contents of an 'IORef', combining 'readIORef' and 'writeIORef'.</span></span>
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<td class="old_line diff-line-num new" data-linenumber="50" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="50" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
50
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC50" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- This is not an atomic update, consider using 'atomicModifyIORef' when</span></span>
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<td class="new_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC51" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- operating in a multithreaded environment.</span></span>
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50
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC52" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
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<td class="new_line diff-line-num" data-linenumber="53" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC53" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- Be warned that 'modifyIORef' does not apply the function strictly.  This</span></span>
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<td class="new_line diff-line-num" data-linenumber="54" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC54" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- means if the program calls 'modifyIORef' many times, but seldom uses the</span></span>
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<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -62,7 +64,9 @@ mkWeakIORef r@(IORef (STRef r#)) (IO finalizer) = IO $ \s -></td>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC64" class="line" lang="haskell"><span class="n" style="color: #333;">modifyIORef</span> <span class="o" style="font-weight: 600;">::</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="p">(</span><span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="n" style="color: #333;">a</span><span class="p">)</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="nb" style="color: #0086b3;">()</span></span>
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<td class="new_line diff-line-num" data-linenumber="65" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC65" class="line" lang="haskell"><span class="n" style="color: #333;">modifyIORef</span> <span class="n" style="color: #333;">ref</span> <span class="n" style="color: #333;">f</span> <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">readIORef</span> <span class="n" style="color: #333;">ref</span> <span class="o" style="font-weight: 600;">>>=</span> <span class="n" style="color: #333;">writeIORef</span> <span class="n" style="color: #333;">ref</span> <span class="o" style="font-weight: 600;">.</span> <span class="n" style="color: #333;">f</span></span>
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64
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<td class="new_line diff-line-num" data-linenumber="66" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC66" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num old" data-linenumber="65" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
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<td class="new_line diff-line-num old" data-linenumber="67" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC65" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Strict version of 'modifyIORef'</span></span>
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<td class="old_line diff-line-num new" data-linenumber="66" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="67" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC67" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Strict version of 'modifyIORef'.</span></span>
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<td class="old_line diff-line-num new" data-linenumber="66" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="68" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC68" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- This is not an atomic update, consider using 'atomicModifyIORef'' when</span></span>
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<td class="new_line diff-line-num new" data-linenumber="69" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC69" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- operating in a multithreaded environment.</span></span>
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<td class="new_line diff-line-num" data-linenumber="70" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC70" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
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<td class="new_line diff-line-num" data-linenumber="71" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC71" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- @since 4.6.0.0</span></span>
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<td class="new_line diff-line-num" data-linenumber="72" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC72" class="line" lang="haskell"><span class="n" style="color: #333;">modifyIORef'</span> <span class="o" style="font-weight: 600;">::</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="p">(</span><span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="n" style="color: #333;">a</span><span class="p">)</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="nb" style="color: #0086b3;">()</span></span>
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<td class="diff-line-num unfold js-unfold new_line" data-linenumber="94" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -90,13 +94,18 @@ modifyIORef' ref f = do</td>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC94" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
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<td class="old_line diff-line-num" data-linenumber="91" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="new_line diff-line-num" data-linenumber="95" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC95" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- Use 'atomicModifyIORef'' or 'atomicWriteIORef' to avoid this problem.</span></span>
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<td class="new_line diff-line-num" data-linenumber="96" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC96" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
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<td class="old_line diff-line-num new" data-linenumber="93" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="97" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC97" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- This function imposes a memory barrier, preventing reordering;</span></span>
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<td class="old_line diff-line-num new" data-linenumber="93" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="98" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
98
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC98" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- see "Data.IORef#memmodel" for details.</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="93" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="99" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
99
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC99" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="93" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
93
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<td class="new_line diff-line-num" data-linenumber="100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
100
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC100" class="line" lang="haskell"><span class="n" style="color: #333;">atomicModifyIORef</span> <span class="o" style="font-weight: 600;">::</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="p">(</span><span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="p">(</span><span class="n" style="color: #333;">a</span><span class="p">,</span><span class="n" style="color: #333;">b</span><span class="p">))</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="n" style="color: #333;">b</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="94" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
94
</td>
<td class="new_line diff-line-num" data-linenumber="101" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
101
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC101" class="line" lang="haskell"><span class="n" style="color: #333;">atomicModifyIORef</span> <span class="n" style="color: #333;">ref</span> <span class="n" style="color: #333;">f</span> <span class="o" style="font-weight: 600;">=</span> <span class="kr" style="font-weight: 600;">do</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="95" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
95
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<td class="new_line diff-line-num" data-linenumber="102" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
102
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC102" class="line" lang="haskell">  <span class="p">(</span><span class="n" style="color: #333;">_old</span><span class="p">,</span> <span class="o" style="font-weight: 600;">~</span><span class="p">(</span><span class="n" style="color: #333;">_new</span><span class="p">,</span> <span class="n" style="color: #333;">res</span><span class="p">))</span> <span class="o" style="font-weight: 600;"><-</span> <span class="n" style="color: #333;">atomicModifyIORef2</span> <span class="n" style="color: #333;">ref</span> <span class="n" style="color: #333;">f</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="96" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
96
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<td class="new_line diff-line-num" data-linenumber="103" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
103
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC103" class="line" lang="haskell">  <span class="n" style="color: #333;">pure</span> <span class="n" style="color: #333;">res</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="97" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
97
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<td class="new_line diff-line-num" data-linenumber="104" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
104
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC104" class="line" lang="haskell"></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="98" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
98
</td>
<td class="new_line diff-line-num old" data-linenumber="105" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC98" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- | Variant of 'writeIORef' with the \"barrier to reordering\" property that</span></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="99" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
99
</td>
<td class="new_line diff-line-num old" data-linenumber="105" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC99" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- 'atomicModifyIORef' has.</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="105" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
105
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC105" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- | Variant of 'writeIORef'. The prefix "atomic" relates to a fact that</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="106" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
106
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC106" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- it imposes a reordering barrier, similar to 'atomicModifyIORef'.</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="107" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
107
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC107" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- Such a write will not be reordered with other reads</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
108
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC108" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- or writes even on CPUs with weak memory model.</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="100" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
100
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<td class="new_line diff-line-num" data-linenumber="109" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
109
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC109" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="101" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
101
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<td class="new_line diff-line-num" data-linenumber="110" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC110" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- @since 4.6.0.0</span></span>
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102
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<td class="new_line diff-line-num" data-linenumber="111" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC111" class="line" lang="haskell"><span class="n" style="color: #333;">atomicWriteIORef</span> <span class="o" style="font-weight: 600;">::</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="nb" style="color: #0086b3;">()</span></span>
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<td class="diff-line-num unfold js-unfold old_line" data-linenumber="105" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="diff-line-num unfold js-unfold new_line" data-linenumber="114" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -105,11 +114,15 @@ atomicWriteIORef ref a = do</td>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC114" class="line" lang="haskell">  <span class="n" style="color: #333;">pure</span> <span class="nb" style="color: #0086b3;">()</span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC115" class="line" lang="haskell"></span>
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107
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<td class="new_line diff-line-num" data-linenumber="116" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC116" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">{- $memmodel</span></span>
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<td class="new_line diff-line-num new" data-linenumber="117" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC117" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  #memmodel#</span></span>
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<td class="new_line diff-line-num new" data-linenumber="118" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC118" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num new" data-linenumber="108" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="119" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
119
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC119" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  Most modern CPU achitectures (e.g. x86/64, ARM) have a memory model which allows</span></span>
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<td class="new_line diff-line-num new" data-linenumber="120" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
120
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC120" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  threads to reorder reads with earlier writes to different locations,</span></span>
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<td class="new_line diff-line-num new" data-linenumber="121" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
121
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC121" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  e.g. see <https://www.intel.com/content/www/us/en/developer/articles/technical/intel-sdm.html the x86/64 architecture manual>,</span></span>
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<td class="new_line diff-line-num new" data-linenumber="122" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC122" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  8.2.3.4 Loads May Be Reordered with Earlier Stores to Different Locations.</span></span>
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108
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123
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC123" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num old" data-linenumber="109" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
109
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<td class="new_line diff-line-num old" data-linenumber="124" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC109" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  In a concurrent program, 'IORef' operations may appear out-of-order</span></span>
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<td class="old_line diff-line-num old" data-linenumber="110" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
110
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<td class="new_line diff-line-num old" data-linenumber="124" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC110" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  to another thread, depending on the memory model of the underlying</span></span>
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<td class="old_line diff-line-num old" data-linenumber="111" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
111
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<td class="new_line diff-line-num old" data-linenumber="124" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC111" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  processor architecture.  For example, on x86, loads can move ahead</span></span>
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<td class="new_line diff-line-num old" data-linenumber="124" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC112" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  of stores, so in the following example:</span></span>
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<td class="old_line diff-line-num new" data-linenumber="113" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="124" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC124" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  Because of that, in a concurrent program, 'IORef' operations may appear out-of-order</span></span>
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<td class="new_line diff-line-num new" data-linenumber="125" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC125" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  to another thread. In the following example:</span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC126" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num" data-linenumber="114" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="new_line diff-line-num" data-linenumber="127" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC127" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  > import Data.IORef</span></span>
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<td class="new_line diff-line-num" data-linenumber="128" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC128" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  > import Control.Monad (unless)</span></span>
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<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -131,20 +144,23 @@ atomicWriteIORef ref a = do</td>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC144" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num" data-linenumber="132" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="new_line diff-line-num" data-linenumber="145" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC145" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  it is possible that the string @"critical section"@ is printed</span></span>
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<td class="new_line diff-line-num" data-linenumber="146" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC146" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  twice, even though there is no interleaving of the operations of the</span></span>
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<td class="old_line diff-line-num old" data-linenumber="134" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
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<td class="new_line diff-line-num old" data-linenumber="147" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC134" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  two threads that allows that outcome.  The memory model of x86</span></span>
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<td class="old_line diff-line-num new" data-linenumber="135" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="147" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC147" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  two threads that allows that outcome.  The memory model of x86<span class="idiff left right addition" style="background-color: #c7f0d2;">/64</span></span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC148" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  allows 'readIORef' to happen before the earlier 'writeIORef'.</span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC149" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num new" data-linenumber="137" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="150" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC150" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  The ARM memory order model is typically even weaker than x86/64, allowing</span></span>
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC151" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  any reordering of reads and writes as long as they are independent</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="137" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="152" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
152
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC152" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  from the point of view of the current thread.</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="137" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="153" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
153
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC153" class="line" lang="haskell"></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="137" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
137
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<td class="new_line diff-line-num" data-linenumber="154" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
154
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC154" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  The implementation is required to ensure that reordering of memory</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="138" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
138
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<td class="new_line diff-line-num" data-linenumber="155" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
155
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC155" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  operations cannot cause type-correct code to go wrong.  In</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="139" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
139
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<td class="new_line diff-line-num" data-linenumber="156" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
156
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC156" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  particular, when inspecting the value read from an 'IORef', the</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="140" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
140
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<td class="new_line diff-line-num" data-linenumber="157" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
157
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC157" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  memory writes that created that value must have occurred from the</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="141" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
141
</td>
<td class="new_line diff-line-num" data-linenumber="158" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
158
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC158" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  point of view of the current thread.</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="142" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
142
</td>
<td class="new_line diff-line-num" data-linenumber="159" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
159
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC159" class="line" lang="haskell"></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="143" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
143
</td>
<td class="new_line diff-line-num old" data-linenumber="160" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC143" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  'atomic<span class="idiff left right deletion" style="background-color: #fac5cd;">ModifyIORef' acts as a barrier to reordering.  Multiple</span></span></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="144" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
144
</td>
<td class="new_line diff-line-num old" data-linenumber="160" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC144" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  <span class="idiff left right deletion" style="background-color: #fac5cd;">'atomicModifyIORef' operations occur in strict program order.  An</span></span></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="145" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
145
</td>
<td class="new_line diff-line-num old" data-linenumber="160" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC145" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  <span class="idiff left deletion" style="background-color: #fac5cd;">'atomicModifyIORef' is never observed to</span> tak<span class="idiff right deletion" style="background-color: #fac5cd;">e</span> place ahead of any</span></span>
</pre></td>
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<tr class="line_holder new" style="line-height: 1.6;">
<td class="old_line diff-line-num new" data-linenumber="146" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="160" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
160
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC160" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  'atomic<span class="idiff left right addition" style="background-color: #c7f0d2;">WriteIORef', 'atomicModifyIORef' and 'atomicModifyIORef'' act</span></span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="146" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="161" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
161
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC161" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  <span class="idiff left right addition" style="background-color: #c7f0d2;">as a barrier to reordering. Multiple calls to these functions</span></span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="146" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="162" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
162
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC162" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  <span class="idiff left addition" style="background-color: #c7f0d2;">occur in strict program order, never</span> tak<span class="idiff right addition" style="background-color: #c7f0d2;">ing</span> place ahead of any</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="146" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
146
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<td class="new_line diff-line-num" data-linenumber="163" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC163" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  earlier (in program order) 'IORef' operations, or after any later</span></span>
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147
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<td class="new_line diff-line-num" data-linenumber="164" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC164" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">  'IORef' operations.</span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC165" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num" data-linenumber="149" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
149
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<td class="new_line diff-line-num" data-linenumber="166" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC166" class="line" lang="haskell"><span class="cm" style="color: #998; font-style: italic;">-}</span></span></pre></td>
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<td class="new_line diff-line-num old" data-linenumber="167" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC150" class="line" lang="haskell"></span></pre></td>
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</li>
<li id="35f0eb539f3f2c545653c8f00151a0d06945215f">
<a href="https://gitlab.haskell.org/ghc/ghc/-/compare/2d4b06ebd34427f711dda87a3b60ba69e5637243...d720c28826afa162c44fea058d15eadeddb877e1#35f0eb539f3f2c545653c8f00151a0d06945215f" style="color: #1068bf;"><strong style="font-weight: bold;">libraries/base/GHC/IORef.hs</strong></a>
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<td class="diff-line-num unfold js-unfold old_line" data-linenumber="32" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="diff-line-num unfold js-unfold new_line" data-linenumber="32" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -32,7 +32,27 @@ import GHC.IO</td>
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<td class="new_line diff-line-num" data-linenumber="32" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC32" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- ---------------------------------------------------------------------------</span></span>
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<td class="old_line diff-line-num" data-linenumber="33" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="new_line diff-line-num" data-linenumber="33" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC33" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- IORefs</span></span>
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<td class="new_line diff-line-num" data-linenumber="34" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC34" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num old" data-linenumber="35" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
35
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<td class="new_line diff-line-num old" data-linenumber="35" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC35" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |A mutable variable in the 'IO' monad</span></span>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="35" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC35" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |A mutable variable in the 'IO' monad.</span></span>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC36" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="37" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC37" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> import Data.IORef</span></span>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="38" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC38" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> r <- newIORef 0</span></span>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="39" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC39" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> readIORef r</span></span>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="40" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC40" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- 0</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="41" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
41
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC41" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> writeIORef r 1</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="42" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
42
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC42" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> readIORef r</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="43" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
43
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC43" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- 1</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="44" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
44
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC44" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> atomicWriteIORef r 2</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="45" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
45
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC45" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> readIORef r</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="46" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
46
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC46" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- 2</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="47" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
47
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC47" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> modifyIORef' r (+ 1)</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="48" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
48
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC48" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> readIORef r</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="49" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
49
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC49" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- 3</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="50" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
50
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC50" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> atomicModifyIORef' r (\a -> (a + 1, ()))</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
51
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC51" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- >>> readIORef r</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="52" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
52
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC52" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- 4</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="53" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
53
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC53" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="54" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
54
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC54" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- See also 'Data.STRef.STRef' and 'Control.Concurrent.MVar.MVar'.</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="36" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="55" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
55
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<td class="new_line diff-line-num" data-linenumber="56" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC56" class="line" lang="haskell"><span class="kr" style="font-weight: 600;">newtype</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">=</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">STRef</span> <span class="kt" style="color: #458; font-weight: 600;">RealWorld</span> <span class="n" style="color: #333;">a</span><span class="p">)</span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC57" class="line" lang="haskell">  <span class="kr" style="font-weight: 600;">deriving</span> <span class="kt" style="color: #458; font-weight: 600;">Eq</span></span>
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38
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<td class="new_line diff-line-num" data-linenumber="58" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC58" class="line" lang="haskell">  <span class="c1" style="color: #998; font-style: italic;">-- ^ Pointer equality.</span></span>
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<td class="diff-line-num unfold js-unfold old_line" data-linenumber="43" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="diff-line-num unfold js-unfold new_line" data-linenumber="63" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -43,11 +63,19 @@ newtype IORef a = IORef (STRef RealWorld a)</td>
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<td class="new_line diff-line-num" data-linenumber="63" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC63" class="line" lang="haskell"><span class="n" style="color: #333;">newIORef</span>    <span class="o" style="font-weight: 600;">::</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span><span class="p">)</span></span>
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<td class="new_line diff-line-num" data-linenumber="64" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC64" class="line" lang="haskell"><span class="n" style="color: #333;">newIORef</span> <span class="n" style="color: #333;">v</span> <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">stToIO</span> <span class="p">(</span><span class="n" style="color: #333;">newSTRef</span> <span class="n" style="color: #333;">v</span><span class="p">)</span> <span class="o" style="font-weight: 600;">>>=</span> <span class="nf" style="color: #900; font-weight: 600;">\</span> <span class="n" style="color: #333;">var</span> <span class="o" style="font-weight: 600;">-></span> <span class="n" style="color: #333;">return</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">var</span><span class="p">)</span></span>
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<td class="new_line diff-line-num" data-linenumber="65" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC65" class="line" lang="haskell"></span>
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<td class="old_line diff-line-num old" data-linenumber="46" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
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<td class="new_line diff-line-num old" data-linenumber="66" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC46" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Read the value of an 'IORef'</span></span>
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<td class="old_line diff-line-num new" data-linenumber="47" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="66" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC66" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Read the value of an 'IORef'.</span></span>
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<td class="old_line diff-line-num new" data-linenumber="47" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="67" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC67" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
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<td class="new_line diff-line-num new" data-linenumber="68" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC68" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- Beware that the CPU executing a thread can reorder reads or writes</span></span>
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<td class="new_line diff-line-num new" data-linenumber="69" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC69" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- to independent locations. See "Data.IORef#memmodel" for more details.</span></span>
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<td class="new_line diff-line-num" data-linenumber="70" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC70" class="line" lang="haskell"><span class="n" style="color: #333;">readIORef</span>   <span class="o" style="font-weight: 600;">::</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="n" style="color: #333;">a</span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC71" class="line" lang="haskell"><span class="n" style="color: #333;">readIORef</span>  <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">var</span><span class="p">)</span> <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">stToIO</span> <span class="p">(</span><span class="n" style="color: #333;">readSTRef</span> <span class="n" style="color: #333;">var</span><span class="p">)</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="49" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
49
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<td class="new_line diff-line-num" data-linenumber="72" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
72
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC72" class="line" lang="haskell"></span>
</pre></td>
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<td class="old_line diff-line-num old" data-linenumber="50" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
50
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<td class="new_line diff-line-num old" data-linenumber="73" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
</td>
<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>-<span id="LC50" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Write a new value into an 'IORef'</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="73" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
73
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC73" class="line" lang="haskell"><span class="cd" style="color: #998; font-style: italic;">-- |Write a new value into an 'IORef'.</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="74" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
74
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC74" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
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<td class="old_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="75" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
75
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC75" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- This function does not create a memory barrier and can be reordered</span></span>
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<td class="old_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="76" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
76
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC76" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- with other independent reads and writes within a thread, which may cause issues</span></span>
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<td class="old_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="77" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC77" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- for multithreaded execution. In these cases, consider using 'Data.IORef.atomicWriteIORef'</span></span>
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<td class="old_line diff-line-num new" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="78" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC78" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- instead. See "Data.IORef#memmodel" for more details.</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="51" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
51
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<td class="new_line diff-line-num" data-linenumber="79" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC79" class="line" lang="haskell"><span class="n" style="color: #333;">writeIORef</span>  <span class="o" style="font-weight: 600;">::</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="nb" style="color: #0086b3;">()</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="52" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
52
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<td class="new_line diff-line-num" data-linenumber="80" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC80" class="line" lang="haskell"><span class="n" style="color: #333;">writeIORef</span> <span class="p">(</span><span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">var</span><span class="p">)</span> <span class="n" style="color: #333;">v</span> <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">stToIO</span> <span class="p">(</span><span class="n" style="color: #333;">writeSTRef</span> <span class="n" style="color: #333;">var</span> <span class="n" style="color: #333;">v</span><span class="p">)</span></span>
</pre></td>
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<td class="new_line diff-line-num" data-linenumber="81" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC81" class="line" lang="haskell"></span>
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<td class="diff-line-num unfold js-unfold old_line" data-linenumber="116" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="diff-line-num unfold js-unfold new_line" data-linenumber="144" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">...</td>
<td class="line_content match" style="color: rgba(0,0,0,0.3); padding: inherit;" bgcolor="#fafafa">@@ -116,6 +144,9 @@ data Box a = Box a</td>
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<td class="old_line diff-line-num" data-linenumber="116" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="new_line diff-line-num" data-linenumber="144" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC144" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- will increment the 'IORef' and then throw an exception in the calling</span></span>
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<td class="new_line diff-line-num" data-linenumber="145" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC145" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- thread.</span></span>
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<td class="old_line diff-line-num" data-linenumber="118" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
118
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<td class="new_line diff-line-num" data-linenumber="146" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
146
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC146" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="119" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="147" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
147
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC147" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- This function imposes a memory barrier, preventing reordering;</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="119" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="148" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
148
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC148" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- see "Data.IORef#memmodel" for details.</span></span>
</pre></td>
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<td class="old_line diff-line-num new" data-linenumber="119" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
</td>
<td class="new_line diff-line-num new" data-linenumber="149" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
149
</td>
<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'>+<span id="LC149" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">--</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="119" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
119
</td>
<td class="new_line diff-line-num" data-linenumber="150" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
150
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC150" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- @since 4.6.0.0</span></span>
</pre></td>
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<td class="old_line diff-line-num" data-linenumber="120" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
120
</td>
<td class="new_line diff-line-num" data-linenumber="151" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
151
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC151" class="line" lang="haskell"><span class="n" style="color: #333;">atomicModifyIORef'</span> <span class="o" style="font-weight: 600;">::</span> <span class="kt" style="color: #458; font-weight: 600;">IORef</span> <span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="p">(</span><span class="n" style="color: #333;">a</span> <span class="o" style="font-weight: 600;">-></span> <span class="p">(</span><span class="n" style="color: #333;">a</span><span class="p">,</span><span class="n" style="color: #333;">b</span><span class="p">))</span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">IO</span> <span class="n" style="color: #333;">b</span></span>
</pre></td>
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<tr class="line_holder" style="line-height: 1.6;">
<td class="old_line diff-line-num" data-linenumber="121" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
121
</td>
<td class="new_line diff-line-num" data-linenumber="152" style="width: 35px; color: rgba(0,0,0,0.3); border-right-width: 1px; border-right-color: #f0f0f0; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fafafa">
152
</td>
<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.8125rem; color: #303030; position: relative; font-family: "Menlo", "DejaVu Sans Mono", "Liberation Mono", "Consolas", "Ubuntu Mono", "Courier New", "andale mono", "lucida console", monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dbdbdb;'> <span id="LC152" class="line" lang="haskell"><span class="c1" style="color: #998; font-style: italic;">-- See Note [atomicModifyIORef' definition]</span></span>
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