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| author | Simon Peyton Jones <simonpj@microsoft.com> | 2021-05-04 08:45:08 +0100 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2021-05-07 09:43:57 -0400 |
| commit | 8e0f48bdd6e83279939d8fdd2ec1e5707725030d (patch) | |
| tree | bc65d57cf1c9b05acc5f54a9627ecfce465e6e0c /compiler/GHC/Tc/Gen/Expr.hs | |
| parent | a664a2ad6432ad19799cf5670311f5d1aaac0559 (diff) | |
| download | haskell-8e0f48bdd6e83279939d8fdd2ec1e5707725030d.tar.gz | |
Allow visible type application for levity-poly data cons
This patch was driven by #18481, to allow visible type application
for levity-polymorphic newtypes. As so often, it started simple
but grew:
* Significant refactor: I removed HsConLikeOut from the
client-independent Language.Haskell.Syntax.Expr, and put it where it
belongs, as a new constructor `ConLikeTc` in the GHC-specific extension
data type for expressions, `GHC.Hs.Expr.XXExprGhcTc`.
That changed touched a lot of files in a very superficial way.
* Note [Typechecking data constructors] explains the main payload.
The eta-expansion part is no longer done by the typechecker, but
instead deferred to the desugarer, via `ConLikeTc`
* A little side benefit is that I was able to restore VTA for
data types with a "stupid theta": #19775. Not very important,
but the code in GHC.Tc.Gen.Head.tcInferDataCon is is much, much
more elegant now.
* I had to refactor the levity-polymorphism checking code in
GHC.HsToCore.Expr, see
Note [Checking for levity-polymorphic functions]
Note [Checking levity-polymorphic data constructors]
Diffstat (limited to 'compiler/GHC/Tc/Gen/Expr.hs')
| -rw-r--r-- | compiler/GHC/Tc/Gen/Expr.hs | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/compiler/GHC/Tc/Gen/Expr.hs b/compiler/GHC/Tc/Gen/Expr.hs index 98d8e8c278..0ff73863cc 100644 --- a/compiler/GHC/Tc/Gen/Expr.hs +++ b/compiler/GHC/Tc/Gen/Expr.hs @@ -329,10 +329,9 @@ tcExpr expr@(ExplicitTuple x tup_args boxity) res_ty ; let expr' = ExplicitTuple x tup_args1 boxity missing_tys = [Scaled mult ty | (Missing (Scaled mult _), ty) <- zip tup_args1 arg_tys] - -- See Note [Linear fields generalization] in GHC.Tc.Gen.App - act_res_ty - = mkVisFunTys missing_tys (mkTupleTy1 boxity arg_tys) - -- See Note [Don't flatten tuples from HsSyn] in GHC.Core.Make + -- See Note [Typechecking data constructors] in GHC.Tc.Gen.Head + -- See Note [Don't flatten tuples from HsSyn] in GHC.Core.Make + act_res_ty = mkVisFunTys missing_tys (mkTupleTy1 boxity arg_tys) ; traceTc "ExplicitTuple" (ppr act_res_ty $$ ppr res_ty) @@ -870,7 +869,6 @@ tcExpr e@(HsRnBracketOut _ brack ps) res_ty = tcUntypedBracket e brack ps res_ty ************************************************************************ -} -tcExpr (HsConLikeOut {}) ty = pprPanic "tcExpr:HsConLikeOut" (ppr ty) tcExpr (HsOverLabel {}) ty = pprPanic "tcExpr:HsOverLabel" (ppr ty) tcExpr (SectionL {}) ty = pprPanic "tcExpr:SectionL" (ppr ty) tcExpr (SectionR {}) ty = pprPanic "tcExpr:SectionR" (ppr ty) |