makeMiniFixityEnv)
import RnEnv ( lookupLocalDataTcNames, lookupLocatedOccRn,
lookupTopBndrRn, lookupLocatedTopBndrRn,
- lookupOccRn, newLocalBndrsRn,
+ lookupOccRn, newLocalBndrsRn, bindLocalNamesFV,
bindLocatedLocalsFV, bindPatSigTyVarsFV,
bindTyVarsRn, extendTyVarEnvFVRn,
bindLocalNames, checkDupRdrNames, mapFvRn
import Outputable
import Bag
import FastString
+import Util ( filterOut )
import SrcLoc
-import DynFlags ( DynFlag(..) )
+import DynFlags ( DynFlag(..) )
import BasicTypes ( Boxity(..) )
-
-import ListSetOps (findDupsEq)
+import ListSetOps ( findDupsEq )
import Control.Monad
import Data.Maybe
tcdLName = tycon, tcdTyVars = tyvars,
tcdTyPats = typatsMaybe, tcdCons = condecls,
tcdKindSig = sig, tcdDerivs = derivs}
- | is_vanilla -- Normal Haskell data type decl
- = ASSERT( isNothing sig ) -- In normal H98 form, kind signature on the
- -- data type is syntactically illegal
- ASSERT( distinctTyVarBndrs tyvars ) -- Tyvars should be distinct
- do { bindTyVarsRn data_doc tyvars $ \ tyvars' -> do
- { tycon' <- if isFamInstDecl tydecl
- then lookupLocatedOccRn tycon -- may be imported family
- else lookupLocatedTopBndrRn tycon
- ; context' <- rnContext data_doc context
- ; typats' <- rnTyPats data_doc typatsMaybe
- ; condecls' <- rnConDecls (unLoc tycon') condecls
- -- No need to check for duplicate constructor decls
- -- since that is done by RnNames.extendGlobalRdrEnvRn
- ; (derivs', deriv_fvs) <- rn_derivs derivs
- ; return (TyData {tcdND = new_or_data, tcdCtxt = context',
- tcdLName = tycon', tcdTyVars = tyvars',
- tcdTyPats = typats', tcdKindSig = Nothing,
- tcdCons = condecls', tcdDerivs = derivs'},
- delFVs (map hsLTyVarName tyvars') $
- extractHsCtxtTyNames context' `plusFV`
- plusFVs (map conDeclFVs condecls') `plusFV`
- deriv_fvs `plusFV`
- (if isFamInstDecl tydecl
- then unitFV (unLoc tycon') -- type instance => use
- else emptyFVs))
- } }
-
- | otherwise -- GADT
= do { tycon' <- if isFamInstDecl tydecl
then lookupLocatedOccRn tycon -- may be imported family
else lookupLocatedTopBndrRn tycon
- ; checkTc (null (unLoc context)) (badGadtStupidTheta tycon)
- ; (tyvars', typats')
+ ; checkTc (h98_style || null (unLoc context))
+ (badGadtStupidTheta tycon)
+ ; (tyvars', context', typats', derivs', deriv_fvs)
<- bindTyVarsRn data_doc tyvars $ \ tyvars' -> do
+ -- Checks for distinct tyvars
{ typats' <- rnTyPats data_doc typatsMaybe
- ; return (tyvars', typats') }
+ ; context' <- rnContext data_doc context
+ ; (derivs', deriv_fvs) <- rn_derivs derivs
+ ; return (tyvars', context', typats', derivs', deriv_fvs) }
-- For GADTs, the type variables in the declaration
-- do not scope over the constructor signatures
-- data T a where { T1 :: forall b. b-> b }
- ; condecls' <- rnConDecls (unLoc tycon') condecls
+ -- For the constructor declarations, bring into scope the tyvars
+ -- bound by the header, but *only* in the H98 case
+ ; let tc_tvs_in_scope | h98_style = hsLTyVarNames tyvars'
+ | otherwise = []
+ ; (condecls', con_fvs) <- bindLocalNamesFV tc_tvs_in_scope $
+ rnConDecls condecls
-- No need to check for duplicate constructor decls
-- since that is done by RnNames.extendGlobalRdrEnvRn
- ; (derivs', deriv_fvs) <- rn_derivs derivs
- ; return (TyData {tcdND = new_or_data, tcdCtxt = noLoc [],
+ ; return (TyData {tcdND = new_or_data, tcdCtxt = context',
tcdLName = tycon', tcdTyVars = tyvars',
tcdTyPats = typats', tcdKindSig = sig,
tcdCons = condecls', tcdDerivs = derivs'},
- plusFVs (map conDeclFVs condecls') `plusFV`
- deriv_fvs `plusFV`
+ con_fvs `plusFV`
+ deriv_fvs `plusFV`
(if isFamInstDecl tydecl
then unitFV (unLoc tycon') -- type instance => use
else emptyFVs))
}
where
- is_vanilla = case condecls of -- Yuk
- [] -> True
+ h98_style = case condecls of
L _ (ConDecl { con_res = ResTyH98 }) : _ -> True
- _ -> False
-
+ _ -> False
data_doc = text "In the data type declaration for" <+> quotes (ppr tycon)
rn_derivs Nothing = return (Nothing, emptyFVs)
-- "type" and "type instance" declarations
rnTyClDecl tydecl@(TySynonym {tcdLName = name, tcdTyVars = tyvars,
tcdTyPats = typatsMaybe, tcdSynRhs = ty})
- = ASSERT( distinctTyVarBndrs tyvars ) -- Tyvars should be distinct
- do { bindTyVarsRn syn_doc tyvars $ \ tyvars' -> do
+ = do { bindTyVarsRn syn_doc tyvars $ \ tyvars' -> do
+ -- Checks for distinct tyvars
{ name' <- if isFamInstDecl tydecl
then lookupLocatedOccRn name -- may be imported family
else lookupLocatedTopBndrRn name
-- Tyvars scope over superclass context and method signatures
; (tyvars', context', fds', ats', ats_fvs, sigs')
<- bindTyVarsRn cls_doc tyvars $ \ tyvars' -> do
+ -- Checks for distinct tyvars
{ context' <- rnContext cls_doc context
; fds' <- rnFds cls_doc fds
; (ats', ats_fvs) <- rnATs ats
cls_doc = text "In the declaration for class" <+> ppr cname
sig_doc = text "In the signatures for class" <+> ppr cname
-distinctTyVarBndrs :: [LHsTyVarBndr RdrName] -> Bool
--- The tyvar binders should have distinct names
-distinctTyVarBndrs tvs
- = null (findDupsEq eq tvs)
- where
- eq (L _ v1) (L _ v2) = hsTyVarName v1 == hsTyVarName v2
-
badGadtStupidTheta :: Located RdrName -> SDoc
badGadtStupidTheta _
= vcat [ptext (sLit "No context is allowed on a GADT-style data declaration"),
%*********************************************************
\begin{code}
+rnTyPats :: SDoc -> Maybe [LHsType RdrName] -> RnM (Maybe [LHsType Name])
-- Although, we are processing type patterns here, all type variables will
-- already be in scope (they are the same as in the 'tcdTyVars' field of the
-- type declaration to which these patterns belong)
---
-rnTyPats :: SDoc -> Maybe [LHsType RdrName] -> RnM (Maybe [LHsType Name])
rnTyPats _ Nothing = return Nothing
rnTyPats doc (Just typats) = liftM Just $ rnLHsTypes doc typats
-rnConDecls :: Name -> [LConDecl RdrName] -> RnM [LConDecl Name]
-rnConDecls _tycon condecls
- = mapM (wrapLocM rnConDecl) condecls
+rnConDecls :: [LConDecl RdrName] -> RnM ([LConDecl Name], FreeVars)
+rnConDecls condecls
+ = do { condecls' <- mapM (wrapLocM rnConDecl) condecls
+ ; return (condecls', plusFVs (map conDeclFVs condecls')) }
rnConDecl :: ConDecl RdrName -> RnM (ConDecl Name)
rnConDecl decl@(ConDecl { con_name = name, con_qvars = tvs
- , con_cxt = cxt, con_details = details
- , con_res = res_ty, con_doc = mb_doc
- , con_old_rec = old_rec, con_explicit = expl })
+ , con_cxt = cxt, con_details = details
+ , con_res = res_ty, con_doc = mb_doc
+ , con_old_rec = old_rec, con_explicit = expl })
= do { addLocM checkConName name
; when old_rec (addWarn (deprecRecSyntax decl))
-
; new_name <- lookupLocatedTopBndrRn name
- ; name_env <- getLocalRdrEnv
-
- -- For H98 syntax, the tvs are the existential ones
- -- For GADT syntax, the tvs are all the quantified tyvars
- -- Hence the 'filter' in the ResTyH98 case only
- ; let not_in_scope = not . (`elemLocalRdrEnv` name_env) . unLoc
- arg_tys = hsConDeclArgTys details
- implicit_tvs = case res_ty of
- ResTyH98 -> filter not_in_scope $
- get_rdr_tvs arg_tys
- ResTyGADT ty -> get_rdr_tvs (ty : arg_tys)
+
+ -- For H98 syntax, the tvs are the existential ones
+ -- For GADT syntax, the tvs are all the quantified tyvars
+ -- Hence the 'filter' in the ResTyH98 case only
+ ; rdr_env <- getLocalRdrEnv
+ ; let in_scope = (`elemLocalRdrEnv` rdr_env) . unLoc
+ arg_tys = hsConDeclArgTys details
+ implicit_tvs = case res_ty of
+ ResTyH98 -> filterOut in_scope (get_rdr_tvs arg_tys)
+ ResTyGADT ty -> get_rdr_tvs (ty : arg_tys)
new_tvs = case expl of
Explicit -> tvs
Implicit -> userHsTyVarBndrs implicit_tvs