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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/TyCl | |
| 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/TyCl')
| -rw-r--r-- | compiler/GHC/Tc/TyCl/Instance.hs | 4 | ||||
| -rw-r--r-- | compiler/GHC/Tc/TyCl/PatSyn.hs | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/compiler/GHC/Tc/TyCl/Instance.hs b/compiler/GHC/Tc/TyCl/Instance.hs index 5a824b0e48..fb83e99583 100644 --- a/compiler/GHC/Tc/TyCl/Instance.hs +++ b/compiler/GHC/Tc/TyCl/Instance.hs @@ -1250,8 +1250,8 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = ibinds }) -- con_app_tys = MkD ty1 ty2 -- con_app_scs = MkD ty1 ty2 sc1 sc2 -- con_app_args = MkD ty1 ty2 sc1 sc2 op1 op2 - con_app_tys = mkHsWrap (mkWpTyApps inst_tys) - (HsConLikeOut noExtField (RealDataCon dict_constr)) + con_app_tys = mkHsWrap (mkWpTyApps inst_tys) $ + mkConLikeTc (RealDataCon dict_constr) -- NB: We *can* have covars in inst_tys, in the case of -- promoted GADT constructors. diff --git a/compiler/GHC/Tc/TyCl/PatSyn.hs b/compiler/GHC/Tc/TyCl/PatSyn.hs index 6f8e1ef901..2ba02e3584 100644 --- a/compiler/GHC/Tc/TyCl/PatSyn.hs +++ b/compiler/GHC/Tc/TyCl/PatSyn.hs @@ -959,7 +959,7 @@ tcPatSynBuilderBind prag_fn (PSB { psb_id = ps_lname@(L loc ps_name) patSynBuilderOcc :: PatSyn -> Maybe (HsExpr GhcTc, TcSigmaType) patSynBuilderOcc ps | Just (_, builder_ty, add_void_arg) <- patSynBuilder ps - , let builder_expr = HsConLikeOut noExtField (PatSynCon ps) + , let builder_expr = mkConLikeTc (PatSynCon ps) = Just $ if add_void_arg then ( builder_expr -- still just return builder_expr; the void# arg |