applyTy, applyTys, isForAllTy, dropForAlls,
-- Source types
applyTy, applyTys, isForAllTy, dropForAlls,
-- Source types
- predTypeRep, mkPredTy, mkPredTys,
- tyConOrigHead, pprSourceTyCon,
+ predTypeRep, mkPredTy, mkPredTys, pprSourceTyCon, mkFamilyTyConApp,
mkTvSubst, mkOpenTvSubst, zipOpenTvSubst, zipTopTvSubst, mkTopTvSubst, notElemTvSubst,
getTvSubstEnv, setTvSubstEnv, getTvInScope, extendTvInScope,
extendTvSubst, extendTvSubstList, isInScope, composeTvSubst, zipTyEnv,
mkTvSubst, mkOpenTvSubst, zipOpenTvSubst, zipTopTvSubst, mkTopTvSubst, notElemTvSubst,
getTvSubstEnv, setTvSubstEnv, getTvInScope, extendTvInScope,
extendTvSubst, extendTvSubstList, isInScope, composeTvSubst, zipTyEnv,
-- Performing substitution on types
substTy, substTys, substTyWith, substTheta,
substPred, substTyVar, substTyVars, substTyVarBndr, deShadowTy, lookupTyVar,
-- Pretty-printing
-- Performing substitution on types
substTy, substTys, substTyWith, substTheta,
substPred, substTyVar, substTyVars, substTyVarBndr, deShadowTy, lookupTyVar,
-- Pretty-printing
- pprType, pprParendType, pprTyThingCategory, pprForAll,
+ pprType, pprParendType, pprTypeApp, pprTyThingCategory, pprForAll,
pprPred, pprTheta, pprThetaArrow, pprClassPred, pprKind, pprParendKind
) where
pprPred, pprTheta, pprThetaArrow, pprClassPred, pprKind, pprParendKind
) where
-- look through that too if necessary
predTypeRep (EqPred ty1 ty2) = pprPanic "predTypeRep" (ppr (EqPred ty1 ty2))
-- look through that too if necessary
predTypeRep (EqPred ty1 ty2) = pprPanic "predTypeRep" (ppr (EqPred ty1 ty2))
--- The original head is the tycon and its variables for a vanilla tycon and it
--- is the family tycon and its type indexes for a family instance.
-tyConOrigHead :: TyCon -> (TyCon, [Type])
-tyConOrigHead tycon = case tyConFamInst_maybe tycon of
- Nothing -> (tycon, mkTyVarTys (tyConTyVars tycon))
- Just famInst -> famInst
+mkFamilyTyConApp :: TyCon -> [Type] -> Type
+-- Given a family instance TyCon and its arg types, return the
+-- corresponding family type. E.g.
+-- data family T a
+-- data instance T (Maybe b) = MkT b -- Instance tycon :RTL
+-- Then
+-- mkFamilyTyConApp :RTL Int = T (Maybe Int)
+mkFamilyTyConApp tc tys
+ | Just (fam_tc, fam_tys) <- tyConFamInst_maybe tc
+ , let fam_subst = zipTopTvSubst (tyConTyVars tc) tys
+ = mkTyConApp fam_tc (substTys fam_subst fam_tys)
+ | otherwise
+ = mkTyConApp tc tys
--- representation tycon.
-pprSourceTyCon tycon | Just (repTyCon, tys) <- tyConFamInst_maybe tycon =
- ppr $ repTyCon `TyConApp` tys -- can't be FunTyCon
- | otherwise =
- ppr tycon
+-- representation tycon. For example
+-- e.g. data T [a] = ...
+-- In that case we want to print `T [a]', where T is the family TyCon
+pprSourceTyCon tycon
+ | Just (fam_tc, tys) <- tyConFamInst_maybe tycon
+ = ppr $ fam_tc `TyConApp` tys -- can't be FunTyCon
+ | otherwise
+ = ppr tycon
- (tidy', occ') -> ((tidy', subst'), tyvar')
- where
- subst' = extendVarEnv subst tyvar tyvar'
- tyvar' = setTyVarName tyvar name'
- name' = tidyNameOcc name occ'
+ (tidy', occ') -> ((tidy', subst'), tyvar'')
+ where
+ subst' = extendVarEnv subst tyvar tyvar''
+ tyvar' = setTyVarName tyvar name'
+ name' = tidyNameOcc name occ'
+ -- Don't forget to tidy the kind for coercions!
+ tyvar'' | isCoVar tyvar = setTyVarKind tyvar' kind'
+ | otherwise = tyvar'
+ kind' = tidyType env (tyVarKind tyvar)