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What's the right way to migrate code? Just switching my library to the new pragmas breaks code, so that doesn't seem very attractive.<o:p></o:p></p>
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I don’t understand. Can you describe the problem more precisely, perhaps with an example?<o:p></o:p></p>
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S<o:p></o:p></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> ghc-devs [mailto:ghc-devs-bounces@haskell.org]
<b>On Behalf Of </b>Johan Tibell<br>
<b>Sent:</b> 25 August 2015 10:42<br>
<b>To:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> OVERLAPPABLE/OVERLAPPING/OVERLAPS pragmas are confusing<o:p></o:p></span></p>
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It was brought to my attention that cassava, my library, uses OverlappingInstances, which is now deprecated. There's a suggested fix here:
<a href="https://github.com/tibbe/cassava/pull/95">https://github.com/tibbe/cassava/pull/95</a>.<o:p></o:p></p>
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The fix seems correct but, as Mikhail points out, makes some client code no longer compile (due to a now missing OVERLAPPABLE pragma).<o:p></o:p></p>
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What's the right way to migrate code? Just switching my library to the new pragmas breaks code, so that doesn't seem very attractive. Do clients have to migrate before the libraries they use?<o:p></o:p></p>
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-- Johan<o:p></o:p></p>
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