diff options
Diffstat (limited to 'compiler/GHC/Iface/Type.hs')
| -rw-r--r-- | compiler/GHC/Iface/Type.hs | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/compiler/GHC/Iface/Type.hs b/compiler/GHC/Iface/Type.hs index 52d07f0fcb..1067e6cab3 100644 --- a/compiler/GHC/Iface/Type.hs +++ b/compiler/GHC/Iface/Type.hs @@ -783,6 +783,22 @@ Here we'd like to omit the kind annotation: type F :: Symbol -> Type type F s = blah + +Note [Printing type abbreviations] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Normally, we pretty-print `TYPE 'LiftedRep` as `Type` (or `*`) and +`FUN 'Many` as `(->)`. +This way, error messages don't refer to levity polymorphism or linearity +if it is not necessary. + +However, when printing the definition of Type or (->) with :info, +this would give confusing output: `type (->) = (->)` (#18594). +Solution: detect when we are in :info and disable displaying the synonym +with the SDoc option sdocPrintTypeAbbreviations. + +If there will be a need, in the future we could expose it as a flag +-fprint-type-abbreviations or even two separate flags controlling +TYPE 'LiftedRep and FUN 'Many. -} -- | Do we want to suppress kind annotations on binders? @@ -1364,12 +1380,14 @@ pprIfaceTypeApp prec tc args = pprTyTcApp prec tc args pprTyTcApp :: PprPrec -> IfaceTyCon -> IfaceAppArgs -> SDoc pprTyTcApp ctxt_prec tc tys = sdocOption sdocPrintExplicitKinds $ \print_kinds -> + sdocOption sdocPrintTypeAbbreviations $ \print_type_abbreviations -> getPprDebug $ \debug -> - pprTyTcApp' ctxt_prec tc tys (PrintExplicitKinds print_kinds) debug + pprTyTcApp' ctxt_prec tc tys (PrintExplicitKinds print_kinds) + print_type_abbreviations debug pprTyTcApp' :: PprPrec -> IfaceTyCon -> IfaceAppArgs - -> PrintExplicitKinds -> Bool -> SDoc -pprTyTcApp' ctxt_prec tc tys printExplicitKinds debug + -> PrintExplicitKinds -> Bool -> Bool -> SDoc +pprTyTcApp' ctxt_prec tc tys printExplicitKinds printTypeAbbreviations debug | ifaceTyConName tc `hasKey` ipClassKey , IA_Arg (IfaceLitTy (IfaceStrTyLit n)) Required (IA_Arg ty Required IA_Nil) <- tys @@ -1393,11 +1411,13 @@ pprTyTcApp' ctxt_prec tc tys printExplicitKinds debug | tc `ifaceTyConHasKey` tYPETyConKey , IA_Arg (IfaceTyConApp rep IA_Nil) Required IA_Nil <- tys , rep `ifaceTyConHasKey` liftedRepDataConKey + , printTypeAbbreviations -- See Note [Printing type abbreviations] = ppr_kind_type ctxt_prec | tc `ifaceTyConHasKey` funTyConKey , IA_Arg (IfaceTyConApp rep IA_Nil) Required args <- tys , rep `ifaceTyConHasKey` manyDataConKey + , printTypeAbbreviations -- See Note [Printing type abbreviations] = pprIfacePrefixApp ctxt_prec (parens arrow) (map (ppr_ty appPrec) (appArgsIfaceTypes $ stripInvisArgs printExplicitKinds args)) | otherwise |