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Diffstat (limited to 'compiler/rename/RnHsSyn.lhs')
| -rw-r--r-- | compiler/rename/RnHsSyn.lhs | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/compiler/rename/RnHsSyn.lhs b/compiler/rename/RnHsSyn.lhs new file mode 100644 index 0000000000..6752218b29 --- /dev/null +++ b/compiler/rename/RnHsSyn.lhs @@ -0,0 +1,156 @@ +% +% (c) The AQUA Project, Glasgow University, 1996-1998 +% +\section[RnHsSyn]{Specialisations of the @HsSyn@ syntax for the renamer} + +\begin{code} +module RnHsSyn( + -- Names + charTyCon_name, listTyCon_name, parrTyCon_name, tupleTyCon_name, + extractHsTyVars, extractHsTyNames, extractHsTyNames_s, + extractFunDepNames, extractHsCtxtTyNames, extractHsPredTyNames, + + -- Free variables + hsSigsFVs, hsSigFVs, conDeclFVs, bangTyFVs, + + maybeGenericMatch + ) where + +#include "HsVersions.h" + +import HsSyn +import Class ( FunDep ) +import TysWiredIn ( tupleTyCon, listTyCon, parrTyCon, charTyCon ) +import Name ( Name, getName, isTyVarName ) +import NameSet +import BasicTypes ( Boxity ) +import SrcLoc ( Located(..), unLoc ) +\end{code} + +%************************************************************************ +%* * +\subsection{Free variables} +%* * +%************************************************************************ + +These free-variable finders returns tycons and classes too. + +\begin{code} +charTyCon_name, listTyCon_name, parrTyCon_name :: Name +charTyCon_name = getName charTyCon +listTyCon_name = getName listTyCon +parrTyCon_name = getName parrTyCon + +tupleTyCon_name :: Boxity -> Int -> Name +tupleTyCon_name boxity n = getName (tupleTyCon boxity n) + +extractHsTyVars :: LHsType Name -> NameSet +extractHsTyVars x = filterNameSet isTyVarName (extractHsTyNames x) + +extractFunDepNames :: FunDep Name -> NameSet +extractFunDepNames (ns1, ns2) = mkNameSet ns1 `unionNameSets` mkNameSet ns2 + +extractHsTyNames :: LHsType Name -> NameSet +extractHsTyNames ty + = getl ty + where + getl (L _ ty) = get ty + + get (HsAppTy ty1 ty2) = getl ty1 `unionNameSets` getl ty2 + get (HsListTy ty) = unitNameSet listTyCon_name `unionNameSets` getl ty + get (HsPArrTy ty) = unitNameSet parrTyCon_name `unionNameSets` getl ty + get (HsTupleTy con tys) = extractHsTyNames_s tys + get (HsFunTy ty1 ty2) = getl ty1 `unionNameSets` getl ty2 + get (HsPredTy p) = extractHsPredTyNames p + get (HsOpTy ty1 op ty2) = getl ty1 `unionNameSets` getl ty2 `unionNameSets` unitNameSet (unLoc op) + get (HsParTy ty) = getl ty + get (HsBangTy _ ty) = getl ty + get (HsNumTy n) = emptyNameSet + get (HsTyVar tv) = unitNameSet tv + get (HsSpliceTy _) = emptyNameSet -- Type splices mention no type variables + get (HsKindSig ty k) = getl ty + get (HsForAllTy _ tvs + ctxt ty) = (extractHsCtxtTyNames ctxt + `unionNameSets` getl ty) + `minusNameSet` + mkNameSet (hsLTyVarNames tvs) + +extractHsTyNames_s :: [LHsType Name] -> NameSet +extractHsTyNames_s tys = foldr (unionNameSets . extractHsTyNames) emptyNameSet tys + +extractHsCtxtTyNames :: LHsContext Name -> NameSet +extractHsCtxtTyNames (L _ ctxt) + = foldr (unionNameSets . extractHsPredTyNames . unLoc) emptyNameSet ctxt + +-- You don't import or export implicit parameters, +-- so don't mention the IP names +extractHsPredTyNames (HsClassP cls tys) + = unitNameSet cls `unionNameSets` extractHsTyNames_s tys +extractHsPredTyNames (HsIParam n ty) + = extractHsTyNames ty +\end{code} + + +%************************************************************************ +%* * +\subsection{Free variables of declarations} +%* * +%************************************************************************ + +Return the Names that must be in scope if we are to use this declaration. +In all cases this is set up for interface-file declarations: + - for class decls we ignore the bindings + - for instance decls likewise, plus the pragmas + - for rule decls, we ignore HsRules + - for data decls, we ignore derivings + + *** See "THE NAMING STORY" in HsDecls **** + +\begin{code} +---------------- +hsSigsFVs :: [LSig Name] -> FreeVars +hsSigsFVs sigs = plusFVs (map (hsSigFVs.unLoc) sigs) + +hsSigFVs (TypeSig v ty) = extractHsTyNames ty +hsSigFVs (SpecInstSig ty) = extractHsTyNames ty +hsSigFVs (SpecSig v ty inl) = extractHsTyNames ty +hsSigFVs other = emptyFVs + +---------------- +conDeclFVs (L _ (ConDecl { con_qvars = tyvars, con_cxt = context, + con_details = details, con_res = res_ty})) + = delFVs (map hsLTyVarName tyvars) $ + extractHsCtxtTyNames context `plusFV` + conDetailsFVs details `plusFV` + conResTyFVs res_ty + +conResTyFVs ResTyH98 = emptyFVs +conResTyFVs (ResTyGADT ty) = extractHsTyNames ty + +conDetailsFVs (PrefixCon btys) = plusFVs (map bangTyFVs btys) +conDetailsFVs (InfixCon bty1 bty2) = bangTyFVs bty1 `plusFV` bangTyFVs bty2 +conDetailsFVs (RecCon flds) = plusFVs [bangTyFVs bty | (_, bty) <- flds] + +bangTyFVs bty = extractHsTyNames (getBangType bty) +\end{code} + + +%************************************************************************ +%* * +\subsection{A few functions on generic defintions +%* * +%************************************************************************ + +These functions on generics are defined over Matches Name, which is +why they are here and not in HsMatches. + +\begin{code} +maybeGenericMatch :: LMatch Name -> Maybe (HsType Name, LMatch Name) + -- Tells whether a Match is for a generic definition + -- and extract the type from a generic match and put it at the front + +maybeGenericMatch (L loc (Match (L _ (TypePat (L _ ty)) : pats) sig_ty grhss)) + = Just (ty, L loc (Match pats sig_ty grhss)) + +maybeGenericMatch other_match = Nothing +\end{code} |