<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html lang="en" style="--code-editor-font: GitLab Mono, JetBrains Mono, Menlo, DejaVu Sans Mono, Liberation Mono, Consolas, Ubuntu Mono, Courier New, andale mono, lucida console, monospace;">
<head>
<meta content="text/html; charset=US-ASCII" http-equiv="Content-Type">
<title>
GitLab
</title>
<style data-premailer="ignore" type="text/css">
a { color: #1068bf; }
</style>
<style>img {
max-width: 100%; height: auto;
}
body {
font-size: 0.875rem;
}
body {
-webkit-text-shadow: rgba(255,255,255,0.01) 0 0 1px;
}
body {
font-family: "GitLab Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans", Ubuntu, Cantarell, "Helvetica Neue", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"; font-size: inherit;
}
</style>
</head>
<body style='font-size: inherit; -webkit-text-shadow: rgba(255,255,255,0.01) 0 0 1px; font-family: "GitLab Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans", Ubuntu, Cantarell, "Helvetica Neue", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";'>
<div class="content">
<h3 style="margin-top: 20px; margin-bottom: 10px;">
Alan Zimmerman pushed to branch wip/az/epa-improve-sl1 at <a href="https://gitlab.haskell.org/ghc/ghc">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/cf86f3ece835ecb389d73760c1d757622c084f0f">cf86f3ec</a></strong>
<div>
<span> by Matthew Craven </span> <i> at 2023-07-16T01:42:09+02:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Equality of forall-types is visibility aware
This patch finally (I hope) nails the question of whether
(forall a. ty) and (forall a -> ty)
are `eqType`: they aren't!
There is a long discussion in #22762, plus useful Notes:
* Note [ForAllTy and type equality] in GHC.Core.TyCo.Compare
* Note [Comparing visiblities] in GHC.Core.TyCo.Compare
* Note [ForAllCo] in GHC.Core.TyCo.Rep
It also establishes a helpful new invariant for ForAllCo,
and ForAllTy, when the bound variable is a CoVar:in that
case the visibility must be coreTyLamForAllTyFlag.
All this is well documented in revised Notes.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/7f13acbf187d7a0810f42705b95d593b1e2e5611">7f13acbf</a></strong>
<div>
<span> by Vladislav Zavialov </span> <i> at 2023-07-16T01:56:27-04:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>List and Tuple<n>: update documentation
Add the missing changelog.md entries and @since-annotations.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/2afbddb0f24df20cfc42279bb8695f91bbd3c1e0">2afbddb0</a></strong>
<div>
<span> by Andrei Borzenkov </span> <i> at 2023-07-16T10:21:24+04:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Type patterns (#22478, #18986)
Improved name resolution and type checking of type patterns in constructors:
1. HsTyPat: a new dedicated data type that represents type patterns in
HsConPatDetails instead of reusing HsPatSigType
2. rnHsTyPat: a new function that renames a type
pattern and collects its binders into three groups:
- explicitly bound type variables, excluding locally bound
variables
- implicitly bound type variables from kind signatures
(only if ScopedTypeVariables are enabled)
- named wildcards (only from kind signatures)
2a. rnHsPatSigTypeBindingVars: removed in favour of rnHsTyPat
2b. rnImplcitTvBndrs: removed because no longer needed
3. collect_pat: updated to collect type variable binders from type patterns
(this means that types and terms use the same infrastructure to detect
conflicting bindings, unused variables and name shadowing)
3a. CollVarTyVarBinders: a new CollectFlag constructor that enables
collection of type variables
4. tcHsTyPat: a new function that typechecks type patterns, capable of
handling polymorphic kinds.
See Note [Type patterns: binders and unifiers]
Examples of code that is now accepted:
f = \(P @a) -> \(P @a) -> ... -- triggers -Wname-shadowing
g :: forall a. Proxy a -> ...
g (P @a) = ... -- also triggers -Wname-shadowing
h (P @($(TH.varT (TH.mkName "t")))) = ...
-- t is bound at splice time
j (P @(a :: (x,x))) = ... -- (x,x) is no longer rejected
data T where
MkT :: forall (f :: forall k. k -> Type).
f Int -> f Maybe -> T
k :: T -> ()
k (MkT @f (x :: f Int) (y :: f Maybe)) = ()
-- f :: forall k. k -> Type
Examples of code that is rejected with better error messages:
f (Left @a @a _) = ...
-- new message:
-- • Conflicting definitions for ‘a’
-- Bound at: Test.hs:1:11
-- Test.hs:1:14
Examples of code that is now rejected:
{-# OPTIONS_GHC -Werror=unused-matches #-}
f (P @a) = ()
-- Defined but not used: type variable ‘a’
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/eb1a6ab1df473c7ec0e1cbb20fc7124706326ce1">eb1a6ab1</a></strong>
<div>
<span> by sheaf </span> <i> at 2023-07-16T09:20:45-04:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Don't use substTyUnchecked in newMetaTyVar
There were some comments that explained that we needed to use an
unchecked substitution function because of issue #12931, but that
has since been fixed, so we should be able to use substTy instead now.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c7bbad9a0aab2d7b4336ae411e13d9450d8483a7">c7bbad9a</a></strong>
<div>
<span> by sheaf </span> <i> at 2023-07-17T02:48:19-04:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>rnImports: var shouldn't import NoFldSelectors
In an import declaration such as
import M ( var )
the import of the variable "var" should **not** bring into scope record
fields named "var" which are defined with NoFieldSelectors.
Doing so can cause spurious "unused import" warnings, as reported in
ticket #23557.
Fixes #23557
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/1af2e7735283251c686bdb1154afab6df5e45053">1af2e773</a></strong>
<div>
<span> by sheaf </span> <i> at 2023-07-17T02:48:19-04:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Suggest similar names in imports
This commit adds similar name suggestions when importing. For example
module A where { spelling = 'o' }
module B where { import B ( speling ) }
will give rise to the error message:
Module ‘A’ does not export ‘speling’.
Suggested fix: Perhaps use ‘spelling’
This also provides hints when users try to import record fields defined
with NoFieldSelectors.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/654fdb989d44e9bdc961f9af7b8171c551b37151">654fdb98</a></strong>
<div>
<span> by Alan Zimmerman </span> <i> at 2023-07-17T02:48:55-04:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>EPA: Store leading AnnSemi for decllist in al_rest
This simplifies the markAnnListA implementation in ExactPrint
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/d328cb00d3938302b8ba32e7a07c0929f2bcdde2">d328cb00</a></strong>
<div>
<span> by Alan Zimmerman </span> <i> at 2023-07-17T17:55:25+01:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>EPA: Improve annotation management in getMonoBind
Ensure the LHsDecl for a FunBind has the correct leading comments and
trailing annotations.
See the added note for details.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/0c4e5953b2ed2e9001f2370e06a3238f7d2f453f">0c4e5953</a></strong>
<div>
<span> by Alan Zimmerman </span> <i> at 2023-07-17T18:03:17+01:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: "GitLab Mono", "JetBrains Mono", "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: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>EPA: Simplify GHC/Parser.y sL1
This is the next patch in a series simplifying location management in
GHC/Parser.y
This one simplifies sL1, to use the HasLoc instances introduced in
!10743 (closed)
</pre>
</li>
</ul>
<h4 style="margin-top: 10px; margin-bottom: 10px;">
30 changed files:
</h4>
<ul>
<li class="file-stats">
<a href="#783e5dae6e86931f06700fc088fb7d48c8a07386">
compiler/GHC/Core/Coercion.hs
</a>
</li>
<li class="file-stats">
<a href="#b0ab2032bd0c006bb9cda1e5433173de35930f53">
compiler/GHC/Core/Coercion.hs-boot
</a>
</li>
<li class="file-stats">
<a href="#975dc08a8e7942b32d621f617d5a9c1b668601dd">
compiler/GHC/Core/Coercion/Opt.hs
</a>
</li>
<li class="file-stats">
<a href="#448d7f6e0151c2014de38dead3a902f511c45b75">
compiler/GHC/Core/FVs.hs
</a>
</li>
<li class="file-stats">
<a href="#36a42448a83a9d1f6df8475f03ead2eed199dd8e">
compiler/GHC/Core/Lint.hs
</a>
</li>
<li class="file-stats">
<a href="#c3967bb9d3e8f5aae2dd111b5a335b48c21c1999">
compiler/GHC/Core/Opt/Arity.hs
</a>
</li>
<li class="file-stats">
<a href="#39b77c6bc34fc853a50f4c1ba3598e2f026625c6">
compiler/GHC/Core/Reduction.hs
</a>
</li>
<li class="file-stats">
<a href="#f12e69f869289252159b0af74c2a0b72b429ab3a">
compiler/GHC/Core/TyCo/Compare.hs
</a>
</li>
<li class="file-stats">
<a href="#039e8f5676356ef05c90af828aae48aac7296e47">
compiler/GHC/Core/TyCo/FVs.hs
</a>
</li>
<li class="file-stats">
<a href="#56394e4c04969cbb82a4624304f94daad39eba96">
compiler/GHC/Core/TyCo/FVs.hs-boot
</a>
</li>
<li class="file-stats">
<a href="#578c7c3857d66d963736ff6742f3433a0e8d01b7">
compiler/GHC/Core/TyCo/Rep.hs
</a>
</li>
<li class="file-stats">
<a href="#8ee6f6851986ea96987a52f1dbf39228c85c6032">
compiler/GHC/Core/TyCo/Subst.hs
</a>
</li>
<li class="file-stats">
<a href="#0b087d030078c501a74df752a832dd50836eb075">
compiler/GHC/Core/TyCo/Tidy.hs
</a>
</li>
<li class="file-stats">
<a href="#84c9d3ba34173297e7d7747e02caa2e004b164fc">
compiler/GHC/Core/Type.hs
</a>
</li>
<li class="file-stats">
<a href="#89a2e0e1a3095c7a42b10f2819049908908080e8">
compiler/GHC/Core/Unify.hs
</a>
</li>
<li class="file-stats">
<a href="#1a7aba0daeafab195716dd25432479804a55ab60">
compiler/GHC/Core/Utils.hs
</a>
</li>
<li class="file-stats">
<a href="#bbf06eb5d4f0db7bc3213b84b9f5822710ff7be8">
compiler/GHC/CoreToIface.hs
</a>
</li>
<li class="file-stats">
<a href="#75bfcd03f3ba9315d33104fcb0424c6bfeb4e334">
compiler/GHC/Hs/Decls.hs
</a>
</li>
<li class="file-stats">
<a href="#9f00edfedb0f969865b049a78de3866545b4a60b">
compiler/GHC/Hs/Instances.hs
</a>
</li>
<li class="file-stats">
<a href="#0bae7e7e67b5f9b6ba2a371f8917cf74423a0c6f">
compiler/GHC/Hs/Pat.hs
</a>
</li>
<li class="file-stats">
<a href="#018be522bc4813b147a1525e4f96a7a493207d96">
compiler/GHC/Hs/Type.hs
</a>
</li>
<li class="file-stats">
<a href="#7a1af22e4c32b9aa6ec708d9d3788e1c4db5da9a">
compiler/GHC/Hs/Utils.hs
</a>
</li>
<li class="file-stats">
<a href="#3c19c0be465f9a28d7b69f89c55648080fcc37eb">
compiler/GHC/HsToCore/Quote.hs
</a>
</li>
<li class="file-stats">
<a href="#649144a78135a23cabfc90dd83c4aabf448eb6ab">
compiler/GHC/Iface/Ext/Ast.hs
</a>
</li>
<li class="file-stats">
<a href="#d11de0586c9bcbcf4c5d10d94801cc1f97e8df1b">
compiler/GHC/Iface/Rename.hs
</a>
</li>
<li class="file-stats">
<a href="#079d6b28856775716c78fdd4a4b35bb45a59002c">
compiler/GHC/Iface/Syntax.hs
</a>
</li>
<li class="file-stats">
<a href="#f2b2b84d138b362920ab9f144f58bf16254aab64">
compiler/GHC/Iface/Type.hs
</a>
</li>
<li class="file-stats">
<a href="#06ff7bac58fd8cfe0c17b81963b03f4cce86a065">
compiler/GHC/IfaceToCore.hs
</a>
</li>
<li class="file-stats">
<a href="#bf951467d4a9aa443cb109cb4c84a2891945649b">
compiler/GHC/Parser.y
</a>
</li>
<li class="file-stats">
<a href="#b1092d2df4ded3655524830252278016d6aa5afd">
compiler/GHC/Parser/Annotation.hs
</a>
</li>
</ul>
<h5 style="margin-top: 10px; margin-bottom: 10px; font-size: 0.875rem;">
The diff was not included because it is too large.
</h5>
</div>
<div class="footer" style="margin-top: 10px;">
<p style="font-size: small; color: #737278;">
—
<br>
<a href="https://gitlab.haskell.org/ghc/ghc/-/compare/a94f64280a6f6a4e1beaf28fc65ce17250cf31e8...0c4e5953b2ed2e9001f2370e06a3238f7d2f453f">View it on GitLab</a>.
<br>
You're receiving this email because of your account on <a target="_blank" rel="noopener noreferrer" href="https://gitlab.haskell.org">gitlab.haskell.org</a>. <a href="https://gitlab.haskell.org/-/profile/notifications" target="_blank" rel="noopener noreferrer" class="mng-notif-link">Manage all notifications</a> · <a href="https://gitlab.haskell.org/help" target="_blank" rel="noopener noreferrer" class="help-link">Help</a>
</p>
</div>
</body>
</html>