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| author | Simon Peyton Jones <simonpj@microsoft.com> | 2021-03-25 16:27:53 +0000 |
|---|---|---|
| committer | Fendor <power.walross@gmail.com> | 2021-04-10 10:35:38 +0200 |
| commit | b014f902c75b9c071b25815b2876adebb2cb5a44 (patch) | |
| tree | bd7291660e69662d64226b944ec69ff542e47e30 /compiler/GHC/Tc/Solver.hs | |
| parent | a951e06921f05df1601d9c3a39efcede27f3330c (diff) | |
| download | haskell-wip/T19296.tar.gz | |
More accurate SrcSpan when reporting redundant constraintswip/T19296
We want an accurate SrcSpan for redundant constraints:
• Redundant constraint: Eq a
• In the type signature for:
f :: forall a. Eq a => a -> ()
|
5 | f :: Eq a => a -> ()
| ^^^^
This patch adds some plumbing to achieve this
* New data type GHC.Tc.Types.Origin.ReportRedundantConstraints (RRC)
* This RRC value is kept inside
- FunSigCtxt
- ExprSigCtxt
* Then, when reporting the error in GHC.Tc.Errors, use this SrcSpan
to control the error message: GHC.Tc.Errors.warnRedundantConstraints
Quite a lot of files are touched in a boring way.
Diffstat (limited to 'compiler/GHC/Tc/Solver.hs')
| -rw-r--r-- | compiler/GHC/Tc/Solver.hs | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/compiler/GHC/Tc/Solver.hs b/compiler/GHC/Tc/Solver.hs index d4e9003b72..5e79a75472 100644 --- a/compiler/GHC/Tc/Solver.hs +++ b/compiler/GHC/Tc/Solver.hs @@ -2042,9 +2042,9 @@ checkBadTelescope (Implic { ic_info = info warnRedundantGivens :: SkolemInfo -> Bool warnRedundantGivens (SigSkol ctxt _ _) = case ctxt of - FunSigCtxt _ warn_redundant -> warn_redundant - ExprSigCtxt -> True - _ -> False + FunSigCtxt _ rrc -> reportRedundantConstraints rrc + ExprSigCtxt rrc -> reportRedundantConstraints rrc + _ -> False -- To think about: do we want to report redundant givens for -- pattern synonyms, PatSynSigSkol? c.f #9953, comment:21. |