kcHsLiftedSigType ty = kcLiftedType ty
tcHsKindedType :: LHsType Name -> TcM Type
- -- Don't do kind checking, nor validity checking,
- -- but do hoist for-alls to the top
+ -- Don't do kind checking, nor validity checking.
-- This is used in type and class decls, where kinding is
-- done in advance, and validity checking is done later
-- [Validity checking done later because of knot-tying issues.]
-- because checkExpectedKind already mentions
-- 'ty' by name in any error message
- ; checkExpectedKind ty act_kind exp_kind
+ ; checkExpectedKind (strip ty) act_kind exp_kind
; return (L span ty') }
where
- -- Wrap a context around only if we want to
- -- show that contexts. Omit invisble ones
- -- and ones user's won't grok (HsPred p).
- add_ctxt (HsPredTy p) thing = thing
- add_ctxt (HsForAllTy Implicit tvs (L _ []) ty) thing = thing
+ -- Wrap a context around only if we want to show that contexts.
+ -- Omit invisble ones and ones user's won't grok (HsPred p).
+ add_ctxt (HsPredTy p) thing = thing
+ add_ctxt (HsForAllTy Implicit tvs (L _ []) (L _ ty)) thing = add_ctxt ty thing
add_ctxt other_ty thing = addErrCtxt (typeCtxt ty) thing
+
+ -- We infer the kind of the type, and then complain if it's
+ -- not right. But we don't want to complain about
+ -- (ty) or !(ty) or forall a. ty
+ -- when the real difficulty is with the 'ty' part.
+ strip (HsParTy (L _ ty)) = strip ty
+ strip (HsBangTy _ (L _ ty)) = strip ty
+ strip (HsForAllTy _ _ _ (L _ ty)) = strip ty
+ strip ty = ty
\end{code}
Here comes the main function
get_largs (L _ ty) args = get_args ty args
get_args (HsAppTy fun arg) args = get_largs fun (arg:args)
get_args (HsParTy ty) args = get_largs ty args
- get_args (HsOpTy ty1 (L span tc) ty2) args = get_args (HsTyVar tc) (ty1:ty2:args)
- get_args ty args = (ty, reverse args)
+ get_args (HsOpTy ty1 (L span tc) ty2) args = (HsTyVar tc, ty1:ty2:args)
+ get_args ty args = (ty, args)
gadtResCtxt ty
= hang (ptext SLIT("In the result type of a data constructor:"))