hsTyVarName, LHsTyVarBndr, LHsType, HsType(..),
mkHsAppTy
)
-import HsTypes ( HsBang(..), getBangStrictness )
+import HsTypes ( HsBang(..), getBangStrictness, hsLTyVarNames )
import BasicTypes ( RecFlag(..), StrictnessMark(..) )
import HscTypes ( implicitTyThings, ModDetails )
import BuildTyCl ( buildClass, buildAlgTyCon, buildSynTyCon, buildDataCon,
tyConDataCons, mkForeignTyCon, isProductTyCon,
isRecursiveTyCon, isOpenTyCon,
tyConStupidTheta, synTyConRhs, isSynTyCon, tyConName,
- isNewTyCon, tyConKind )
+ isNewTyCon, isDataTyCon, tyConKind,
+ setTyConArgPoss )
import DataCon ( DataCon, dataConUserType, dataConName,
dataConFieldLabels, dataConTyCon, dataConAllTyVars,
dataConFieldType, dataConResTys )
import VarSet ( elemVarSet, mkVarSet )
import Name ( Name, getSrcLoc )
import Outputable
-import Maybe ( isJust, fromJust, isNothing )
+import Maybe ( isJust, fromJust, isNothing, catMaybes )
import Maybes ( expectJust )
+import Monad ( unless )
import Unify ( tcMatchTys, tcMatchTyX )
import Util ( zipLazy, isSingleton, notNull, sortLe )
-import List ( partition )
+import List ( partition, elemIndex )
import SrcLoc ( Located(..), unLoc, getLoc, srcLocSpan )
import ListSetOps ( equivClasses, minusList )
-import List ( delete )
import Digraph ( SCC(..) )
import DynFlags ( DynFlag( Opt_GlasgowExts, Opt_Generics,
Opt_UnboxStrictFields ) )
-> TcM (Maybe InstInfo, Maybe TyThing) -- Nothing if error
tcIdxTyInstDecl1 (decl@TySynonym {})
- = kcIdxTyPats decl $ \k_tvs k_typats resKind _ ->
- do { -- (1) kind check the right hand side of the type equation
+ = kcIdxTyPats decl $ \k_tvs k_typats resKind family ->
+ do { -- check that the family declaration is for a synonym
+ unless (isSynTyCon family) $
+ addErr (wrongKindOfFamily family)
+
+ ; -- (1) kind check the right hand side of the type equation
; k_rhs <- kcCheckHsType (tcdSynRhs decl) resKind
-- (2) type check type equation
tcIdxTyInstDecl1 (decl@TyData {tcdND = new_or_data, tcdLName = L loc tc_name,
tcdCons = cons})
= kcIdxTyPats decl $ \k_tvs k_typats resKind family ->
- do { -- (1) kind check the data declaration as usual
+ do { -- check that the family declaration is for the right kind
+ unless (new_or_data == NewType && isNewTyCon family ||
+ new_or_data == DataType && isDataTyCon family) $
+ addErr (wrongKindOfFamily family)
+
+ ; -- (1) kind check the data declaration as usual
; k_decl <- kcDataDecl decl k_tvs
; let k_ctxt = tcdCtxt k_decl
k_cons = tcdCons k_decl
; tycon <- fixM (\ tycon -> do
{ data_cons <- mappM (addLocM (tcConDecl unbox_strict new_or_data
- tycon t_tvs (Just t_typats)))
+ tycon t_tvs))
k_cons
; tc_rhs <-
case new_or_data of
ASSERT( isSingleton data_cons )
mkNewTyConRhs tc_name tycon (head data_cons)
; buildAlgTyCon tc_name t_tvs stupid_theta tc_rhs Recursive
- False h98_syntax (Just family)
+ False h98_syntax (Just (family, t_typats))
-- We always assume that indexed types are recursive. Why?
-- (1) Due to their open nature, we can never be sure that a
-- further instance might not introduce a new recursive
})
-- construct result
- -- !!!TODO: missing eq axiom
; return (Nothing, Just (ATyCon tycon))
}}
where
-- Check that we don't use kind signatures without Glasgow extensions
; checkTc gla_exts $ badSigTyDecl tc_name
- ; return [ATyCon (buildSynTyCon tc_name tvs' (OpenSynTyCon kind))]
+ ; return [ATyCon $ buildSynTyCon tc_name tvs' (OpenSynTyCon kind)]
}
-- kind signature for an indexed data type
; tycon <- fixM (\ tycon -> do
{ data_cons <- mappM (addLocM (tcConDecl unbox_strict new_or_data
- tycon final_tvs Nothing))
+ tycon final_tvs))
cons
; tc_rhs <-
if null cons && is_boot -- In a hs-boot file, empty cons means
{ ctxt' <- tcHsKindedContext ctxt
; fds' <- mappM (addLocM tc_fundep) fundeps
; atss <- mappM (addLocM (tcTyClDecl1 (const Recursive))) ats
- ; let ats' = concat atss
+ ; let ats' = zipWith setTyThingPoss atss (map (tcdTyVars . unLoc) ats)
; sig_stuff <- tcClassSigs class_name sigs meths
; clas <- fixM (\ clas ->
let -- This little knot is just so we can get
; tvs2' <- mappM tcLookupTyVar tvs2 ;
; return (tvs1', tvs2') }
+ -- For each AT argument compute the position of the corresponding class
+ -- parameter in the class head. This will later serve as a permutation
+ -- vector when checking the validity of instance declarations.
+ setTyThingPoss [ATyCon tycon] atTyVars =
+ let classTyVars = hsLTyVarNames tvs
+ poss = catMaybes
+ . map (`elemIndex` classTyVars)
+ . hsLTyVarNames
+ $ atTyVars
+ -- There will be no Nothing, as we already passed renaming
+ in
+ ATyCon (setTyConArgPoss tycon poss)
+ setTyThingPoss _ _ = panic "TcTyClsDecls.setTyThingPoss"
tcTyClDecl1 calc_isrec
(ForeignType {tcdLName = L _ tc_name, tcdExtName = tc_ext_name})
tcConDecl :: Bool -- True <=> -funbox-strict_fields
-> NewOrData
-> TyCon -> [TyVar]
- -> Maybe [Type] -- Just ts <=> type patterns of instance type
-> ConDecl Name
-> TcM DataCon
-tcConDecl unbox_strict NewType tycon tc_tvs mb_typats -- Newtypes
+tcConDecl unbox_strict NewType tycon tc_tvs -- Newtypes
(ConDecl name _ ex_tvs ex_ctxt details ResTyH98)
= do { let tc_datacon field_lbls arg_ty
= do { arg_ty' <- tcHsKindedType arg_ty -- No bang on newtype
tc_tvs [] -- No existentials
[] [] -- No equalities, predicates
[arg_ty']
- tycon
- mb_typats}
+ tycon }
-- Check that a newtype has no existential stuff
; checkTc (null ex_tvs && null (unLoc ex_ctxt)) (newtypeExError name)
-- Check that the constructor has exactly one field
}
-tcConDecl unbox_strict DataType tycon tc_tvs mb_typats -- Data types
+tcConDecl unbox_strict DataType tycon tc_tvs -- Data types
(ConDecl name _ tvs ctxt details res_ty)
= tcTyVarBndrs tvs $ \ tvs' -> do
{ ctxt' <- tcHsKindedContext ctxt
(argStrictness unbox_strict tycon bangs arg_tys)
(map unLoc field_lbls)
univ_tvs ex_tvs eq_preds ctxt' arg_tys
- data_tc
- mb_typats}
+ data_tc }
-- NB: we put data_tc, the type constructor gotten from the
-- constructor type signature into the data constructor;
-- that way checkValidDataCon can complain if it's wrong.
= ptext SLIT("Indexed type instance has too few parameters:") <+>
quotes (ppr tc_name)
-badBootTyIdxDeclErr = ptext SLIT("Illegal indexed type instance in hs-boot file")
+badBootTyIdxDeclErr =
+ ptext SLIT("Illegal indexed type instance in hs-boot file")
+
+wrongKindOfFamily family =
+ ptext SLIT("Wrong category of type instance; declaration was for a") <+>
+ kindOfFamily
+ where
+ kindOfFamily | isSynTyCon family = ptext SLIT("type synonym")
+ | isDataTyCon family = ptext SLIT("data type")
+ | isNewTyCon family = ptext SLIT("newtype")
emptyConDeclsErr tycon
= sep [quotes (ppr tycon) <+> ptext SLIT("has no constructors"),