diff options
Diffstat (limited to 'compiler/typecheck/TcMType.hs')
| -rw-r--r-- | compiler/typecheck/TcMType.hs | 26 |
1 files changed, 19 insertions, 7 deletions
diff --git a/compiler/typecheck/TcMType.hs b/compiler/typecheck/TcMType.hs index 0ac553c0ea..49833ac773 100644 --- a/compiler/typecheck/TcMType.hs +++ b/compiler/typecheck/TcMType.hs @@ -17,6 +17,7 @@ module TcMType ( -------------------------------- -- Creating new mutable type variables newFlexiTyVar, + newNamedFlexiTyVar, newFlexiTyVarTy, -- Kind -> TcM TcType newFlexiTyVarTys, -- Int -> Kind -> TcM [TcType] newOpenFlexiTyVarTy, newOpenTypeKind, @@ -730,15 +731,22 @@ And there no reason /not/ to clone the Name when making a unification variable. So that's what we do. -} +metaInfoToTyVarName :: MetaInfo -> FastString +metaInfoToTyVarName meta_info = + case meta_info of + TauTv -> fsLit "t" + FlatMetaTv -> fsLit "fmv" + FlatSkolTv -> fsLit "fsk" + TyVarTv -> fsLit "a" + newAnonMetaTyVar :: MetaInfo -> Kind -> TcM TcTyVar +newAnonMetaTyVar mi = newNamedAnonMetaTyVar (metaInfoToTyVarName mi) mi + +newNamedAnonMetaTyVar :: FastString -> MetaInfo -> Kind -> TcM TcTyVar -- Make a new meta tyvar out of thin air -newAnonMetaTyVar meta_info kind - = do { let s = case meta_info of - TauTv -> fsLit "t" - FlatMetaTv -> fsLit "fmv" - FlatSkolTv -> fsLit "fsk" - TyVarTv -> fsLit "a" - ; name <- newMetaTyVarName s +newNamedAnonMetaTyVar tyvar_name meta_info kind + + = do { name <- newMetaTyVarName tyvar_name ; details <- newMetaDetails meta_info ; let tyvar = mkTcTyVar name kind details ; traceTc "newAnonMetaTyVar" (ppr tyvar) @@ -963,6 +971,10 @@ that can't ever appear in user code, so we're safe! newFlexiTyVar :: Kind -> TcM TcTyVar newFlexiTyVar kind = newAnonMetaTyVar TauTv kind +-- | Create a new flexi ty var with a specific name +newNamedFlexiTyVar :: FastString -> Kind -> TcM TcTyVar +newNamedFlexiTyVar fs kind = newNamedAnonMetaTyVar fs TauTv kind + newFlexiTyVarTy :: Kind -> TcM TcType newFlexiTyVarTy kind = do tc_tyvar <- newFlexiTyVar kind |