mkFunTy, mkFunTys, splitFunTy, splitFunTy_maybe,
splitFunTys, splitFunTysN,
- funResultTy, funArgTy, zipFunTys,
+ funResultTy, funArgTy, zipFunTys,
mkTyConApp, mkTyConTy,
tyConAppTyCon, tyConAppArgs,
tyFamInsts, predFamInsts,
-- (Source types)
- mkPredTy, mkPredTys, mkFamilyTyConApp, isEqPred,
+ mkPredTy, mkPredTys, mkFamilyTyConApp, isEqPred, coVarPred,
-- ** Common type constructors
funTyCon,
tyVarsOfType, tyVarsOfTypes, tyVarsOfPred, tyVarsOfTheta,
expandTypeSynonyms,
- -- * Tidying type related things up for printing
- tidyType, tidyTypes,
- tidyOpenType, tidyOpenTypes,
- tidyTyVarBndr, tidyFreeTyVars,
- tidyOpenTyVar, tidyOpenTyVars,
- tidyTopType, tidyPred,
- tidyKind,
-
-- * Type comparison
coreEqType, coreEqType2,
tcEqType, tcEqTypes, tcCmpType, tcCmpTypes,
getTvSubstEnv, setTvSubstEnv, zapTvSubstEnv, getTvInScope,
extendTvInScope, extendTvInScopeList,
extendTvSubst, extendTvSubstList, isInScope, composeTvSubst, zipTyEnv,
- isEmptyTvSubst,
+ isEmptyTvSubst, unionTvSubst,
-- ** Performing substitution on types
substTy, substTys, substTyWith, substTysWith, substTheta,
import VarEnv
import VarSet
-import Name
import Class
import TyCon
import Outputable
import FastString
-import Data.List
import Data.Maybe ( isJust )
+
+infixr 3 `mkFunTy` -- Associates to the right
\end{code}
\begin{code}
splitFunTysN :: Int -> Type -> ([Type], Type)
-- ^ Split off exactly the given number argument types, and panics if that is not possible
splitFunTysN 0 ty = ([], ty)
-splitFunTysN n ty = case splitFunTy ty of { (arg, res) ->
+splitFunTysN n ty = ASSERT2( isFunTy ty, int n <+> ppr ty )
+ case splitFunTy ty of { (arg, res) ->
case splitFunTysN (n-1) res of { (args, res) ->
(arg:args, res) }}
\begin{code}
tyVarsOfType :: Type -> TyVarSet
-- ^ NB: for type synonyms tyVarsOfType does /not/ expand the synonym
-tyVarsOfType (TyVarTy tv) = unitVarSet tv
-tyVarsOfType (TyConApp _ tys) = tyVarsOfTypes tys
-tyVarsOfType (PredTy sty) = tyVarsOfPred sty
-tyVarsOfType (FunTy arg res) = tyVarsOfType arg `unionVarSet` tyVarsOfType res
-tyVarsOfType (AppTy fun arg) = tyVarsOfType fun `unionVarSet` tyVarsOfType arg
-tyVarsOfType (ForAllTy tyvar ty) = delVarSet (tyVarsOfType ty) tyvar
+tyVarsOfType (TyVarTy tv) = unitVarSet tv
+tyVarsOfType (TyConApp _ tys) = tyVarsOfTypes tys
+tyVarsOfType (PredTy sty) = tyVarsOfPred sty
+tyVarsOfType (FunTy arg res) = tyVarsOfType arg `unionVarSet` tyVarsOfType res
+tyVarsOfType (AppTy fun arg) = tyVarsOfType fun `unionVarSet` tyVarsOfType arg
+tyVarsOfType (ForAllTy tv ty) -- The kind of a coercion binder
+ -- can mention type variables!
+ | isTyVar tv = inner_tvs `delVarSet` tv
+ | otherwise {- Coercion -} = -- ASSERT( not (tv `elemVarSet` inner_tvs) )
+ inner_tvs `unionVarSet` tyVarsOfType (tyVarKind tv)
+ where
+ inner_tvs = tyVarsOfType ty
tyVarsOfTypes :: [Type] -> TyVarSet
tyVarsOfTypes tys = foldr (unionVarSet.tyVarsOfType) emptyVarSet tys
| Just exp_ty <- tcView ty = tyFamInsts exp_ty
tyFamInsts (TyVarTy _) = []
tyFamInsts (TyConApp tc tys)
- | isOpenSynTyCon tc = [(tc, tys)]
+ | isSynFamilyTyCon tc = [(tc, tys)]
| otherwise = concat (map tyFamInsts tys)
tyFamInsts (FunTy ty1 ty2) = tyFamInsts ty1 ++ tyFamInsts ty2
tyFamInsts (AppTy ty1 ty2) = tyFamInsts ty1 ++ tyFamInsts ty2
%************************************************************************
%* *
-\subsection{TidyType}
-%* *
-%************************************************************************
-
-\begin{code}
--- | This tidies up a type for printing in an error message, or in
--- an interface file.
---
--- It doesn't change the uniques at all, just the print names.
-tidyTyVarBndr :: TidyEnv -> TyVar -> (TidyEnv, TyVar)
-tidyTyVarBndr env@(tidy_env, subst) tyvar
- = case tidyOccName tidy_env (getOccName name) of
- (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)
- where
- name = tyVarName tyvar
-
-tidyFreeTyVars :: TidyEnv -> TyVarSet -> TidyEnv
--- ^ Add the free 'TyVar's to the env in tidy form,
--- so that we can tidy the type they are free in
-tidyFreeTyVars env tyvars = fst (tidyOpenTyVars env (varSetElems tyvars))
-
-tidyOpenTyVars :: TidyEnv -> [TyVar] -> (TidyEnv, [TyVar])
-tidyOpenTyVars env tyvars = mapAccumL tidyOpenTyVar env tyvars
-
-tidyOpenTyVar :: TidyEnv -> TyVar -> (TidyEnv, TyVar)
--- ^ Treat a new 'TyVar' as a binder, and give it a fresh tidy name
--- using the environment if one has not already been allocated. See
--- also 'tidyTyVarBndr'
-tidyOpenTyVar env@(_, subst) tyvar
- = case lookupVarEnv subst tyvar of
- Just tyvar' -> (env, tyvar') -- Already substituted
- Nothing -> tidyTyVarBndr env tyvar -- Treat it as a binder
-
-tidyType :: TidyEnv -> Type -> Type
-tidyType env@(_, subst) ty
- = go ty
- where
- go (TyVarTy tv) = case lookupVarEnv subst tv of
- Nothing -> TyVarTy tv
- Just tv' -> TyVarTy tv'
- go (TyConApp tycon tys) = let args = map go tys
- in args `seqList` TyConApp tycon args
- go (PredTy sty) = PredTy (tidyPred env sty)
- go (AppTy fun arg) = (AppTy $! (go fun)) $! (go arg)
- go (FunTy fun arg) = (FunTy $! (go fun)) $! (go arg)
- go (ForAllTy tv ty) = ForAllTy tvp $! (tidyType envp ty)
- where
- (envp, tvp) = tidyTyVarBndr env tv
-
-tidyTypes :: TidyEnv -> [Type] -> [Type]
-tidyTypes env tys = map (tidyType env) tys
-
-tidyPred :: TidyEnv -> PredType -> PredType
-tidyPred env (IParam n ty) = IParam n (tidyType env ty)
-tidyPred env (ClassP clas tys) = ClassP clas (tidyTypes env tys)
-tidyPred env (EqPred ty1 ty2) = EqPred (tidyType env ty1) (tidyType env ty2)
-\end{code}
-
-
-\begin{code}
--- | Grabs the free type variables, tidies them
--- and then uses 'tidyType' to work over the type itself
-tidyOpenType :: TidyEnv -> Type -> (TidyEnv, Type)
-tidyOpenType env ty
- = (env', tidyType env' ty)
- where
- env' = tidyFreeTyVars env (tyVarsOfType ty)
-
-tidyOpenTypes :: TidyEnv -> [Type] -> (TidyEnv, [Type])
-tidyOpenTypes env tys = mapAccumL tidyOpenType env tys
-
--- | Calls 'tidyType' on a top-level type (i.e. with an empty tidying environment)
-tidyTopType :: Type -> Type
-tidyTopType ty = tidyType emptyTidyEnv ty
-\end{code}
-
-\begin{code}
-
-tidyKind :: TidyEnv -> Kind -> (TidyEnv, Kind)
-tidyKind env k = tidyOpenType env k
-
-\end{code}
-
-
-%************************************************************************
-%* *
\subsection{Liftedness}
%* *
%************************************************************************
isClosedAlgType ty
= case splitTyConApp_maybe ty of
Just (tc, ty_args) -> ASSERT( ty_args `lengthIs` tyConArity tc )
- isAlgTyCon tc && not (isOpenTyCon tc)
+ isAlgTyCon tc && not (isFamilyTyCon tc)
_other -> False
\end{code}
For example, consider:
(/\a. /\b:(a~Int). ...b..) Int
We substitute Int for 'a'. The Unique of 'b' does not change, but
-nevertheless we add 'b' to the TvSubstEnv, because b's type does change
+nevertheless we add 'b' to the TvSubstEnv, because b's kind does change
This invariant has several crucial consequences:
extendTvSubstList (TvSubst in_scope env) tvs tys
= TvSubst in_scope (extendVarEnvList env (tvs `zip` tys))
+unionTvSubst :: TvSubst -> TvSubst -> TvSubst
+-- Works when the ranges are disjoint
+unionTvSubst (TvSubst in_scope1 env1) (TvSubst in_scope2 env2)
+ = ASSERT( not (env1 `intersectsVarEnv` env2) )
+ TvSubst (in_scope1 `unionInScope` in_scope2)
+ (env1 `plusVarEnv` env2)
+
-- mkOpenTvSubst and zipOpenTvSubst generate the in-scope set from
-- the types given; but it's just a thunk so with a bit of luck
-- it'll never be evaluated