module TcTyDecls (
tcTyDecl,
tcConDecl,
- tcRecordSelectors
+ mkDataBinds
) where
-import Ubiq{-uitous-}
+IMP_Ubiq(){-uitous-}
import HsSyn ( TyDecl(..), ConDecl(..), BangType(..), HsExpr(..),
Match(..), GRHSsAndBinds(..), GRHS(..), OutPat(..),
- HsBinds(..), HsLit, Stmt, Qual, ArithSeqInfo, PolyType,
+ HsBinds(..), HsLit, Stmt, Qualifier, ArithSeqInfo,
+ PolyType, Fake, InPat,
Bind(..), MonoBinds(..), Sig,
MonoType )
-import RnHsSyn ( RenamedTyDecl(..), RenamedConDecl(..) )
-import TcHsSyn ( TcHsBinds(..), TcIdOcc(..), mkHsTyLam )
-
-import TcMonoType ( tcMonoTypeKind, tcMonoType, tcContext )
-import TcType ( tcInstTyVars, tcInstType )
+import RnHsSyn ( RenamedTyDecl(..), RenamedConDecl(..),
+ RnName{-instance Outputable-}
+ )
+import TcHsSyn ( mkHsTyLam, mkHsDictLam, tcIdType,
+ SYN_IE(TcHsBinds), TcIdOcc(..)
+ )
+import Inst ( newDicts, InstOrigin(..), Inst )
+import TcMonoType ( tcMonoTypeKind, tcMonoType, tcPolyType, tcContext )
+import TcSimplify ( tcSimplifyThetas )
+import TcType ( tcInstTyVars, tcInstType, tcInstId )
import TcEnv ( tcLookupTyCon, tcLookupTyVar, tcLookupClass,
- newLocalId
+ newLocalId, newLocalIds, tcLookupClassByKey
)
-import TcMonad
+import TcMonad hiding ( rnMtoTcM )
import TcKind ( TcKind, unifyKind, mkTcArrowKind, mkTcTypeKind )
-import Id ( mkDataCon, dataConSig, mkRecordSelectorId,
- dataConFieldLabels, StrictnessMark(..)
+import PprType ( GenClass, GenType{-instance Outputable-},
+ GenTyVar{-instance Outputable-}{-ToDo:possibly rm-}
+ )
+import Class ( GenClass{-instance Eq-}, classInstEnv )
+import Id ( mkDataCon, dataConSig, mkRecordSelId, idType,
+ dataConFieldLabels, dataConStrictMarks,
+ StrictnessMark(..),
+ GenId{-instance NamedThing-}
)
import FieldLabel
import Kind ( Kind, mkArrowKind, mkBoxedTypeKind )
-import SpecEnv ( SpecEnv(..), nullSpecEnv )
-import Name ( getNameFullName, Name(..) )
+import SpecEnv ( SpecEnv, nullSpecEnv )
+import Name ( nameSrcLoc, isLocallyDefinedName, getSrcLoc,
+ Name{-instance Ord3-}
+ )
+import Outputable ( Outputable(..), interpp'SP )
import Pretty
-import TyCon ( TyCon, NewOrData(..), mkSynTyCon, mkDataTyCon, tyConDataCons )
-import Type ( getTypeKind, getTyVar, tyVarsOfTypes, eqTy, applyTyCon,
- mkForAllTys, mkFunTy )
-import TyVar ( getTyVarKind, elementOfTyVarSet )
-import UniqSet ( emptyUniqSet, mkUniqSet, uniqSetToList, unionManyUniqSets, UniqSet(..) )
-import Util ( panic, equivClasses )
+import TyCon ( TyCon, NewOrData(..), mkSynTyCon, mkDataTyCon, isDataTyCon,
+ isNewTyCon, isSynTyCon, tyConDataCons
+ )
+import Type ( GenType, -- instances
+ typeKind, getTyVar, tyVarsOfTypes, eqTy, splitSigmaTy,
+ applyTyCon, mkTyVarTys, mkForAllTys, mkFunTy,
+ splitFunTy, mkTyVarTy, getTyVar_maybe
+ )
+import TyVar ( tyVarKind, elementOfTyVarSet, GenTyVar{-instance Eq-} )
+import Unique ( Unique {- instance Eq -}, evalClassKey )
+import UniqSet ( emptyUniqSet, mkUniqSet, uniqSetToList, unionManyUniqSets, SYN_IE(UniqSet) )
+import Util ( equivClasses, zipEqual, nOfThem, panic, assertPanic )
\end{code}
\begin{code}
-- but the simplest thing to do seems to be to get the Kind by (lazily)
-- looking at the tyvars and rhs_ty.
result_kind, final_tycon_kind :: Kind -- NB not TcKind!
- result_kind = getTypeKind rhs_ty
- final_tycon_kind = foldr (mkArrowKind . getTyVarKind) result_kind rec_tyvars
+ result_kind = typeKind rhs_ty
+ final_tycon_kind = foldr (mkArrowKind . tyVarKind) result_kind rec_tyvars
-- Construct the tycon
- tycon = mkSynTyCon (getItsUnique tycon_name)
- (getNameFullName tycon_name)
+ tycon = mkSynTyCon (getName tycon_name)
final_tycon_kind
(length tyvar_names)
rec_tyvars
let
-- Construct the tycon
final_tycon_kind :: Kind -- NB not TcKind!
- final_tycon_kind = foldr (mkArrowKind . getTyVarKind) mkBoxedTypeKind rec_tyvars
+ final_tycon_kind = foldr (mkArrowKind . tyVarKind) mkBoxedTypeKind rec_tyvars
- tycon = mkDataTyCon (getItsUnique tycon_name)
+ tycon = mkDataTyCon (getName tycon_name)
final_tycon_kind
- (getNameFullName tycon_name)
rec_tyvars
ctxt
con_ids
returnNF_Tc clas
\end{code}
-Generating selector bindings for record delarations
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Generating constructor/selector bindings for data declarations
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
\begin{code}
-tcRecordSelectors :: TyCon -> TcM s ([Id], TcHsBinds s)
-tcRecordSelectors tycon
- = mapAndUnzipTc (tcRecordSelector tycon) groups `thenTc` \ (ids, binds) ->
- returnTc (ids, SingleBind (NonRecBind (foldr AndMonoBinds EmptyMonoBinds binds)))
+mkDataBinds :: [TyCon] -> TcM s ([Id], TcHsBinds s)
+mkDataBinds [] = returnTc ([], EmptyBinds)
+mkDataBinds (tycon : tycons)
+ | isSynTyCon tycon = mkDataBinds tycons
+ | otherwise = mkDataBinds_one tycon `thenTc` \ (ids1, b1) ->
+ mkDataBinds tycons `thenTc` \ (ids2, b2) ->
+ returnTc (ids1++ids2, b1 `ThenBinds` b2)
+
+mkDataBinds_one tycon
+ = ASSERT( isDataTyCon tycon || isNewTyCon tycon )
+ mapAndUnzipTc mkConstructor data_cons `thenTc` \ (con_ids, con_binds) ->
+ mapAndUnzipTc (mkRecordSelector tycon) groups `thenTc` \ (sel_ids, sel_binds) ->
+ returnTc (con_ids ++ sel_ids,
+ SingleBind $ NonRecBind $
+ foldr AndMonoBinds
+ (foldr AndMonoBinds EmptyMonoBinds sel_binds)
+ con_binds
+ )
where
data_cons = tyConDataCons tycon
fields = [ (con, field) | con <- data_cons,
= fieldLabelName field1 `cmp` fieldLabelName field2
\end{code}
+We're going to build a constructor that looks like:
+
+ data (Data a, C b) => T a b = T1 !a !Int b
+
+ T1 = /\ a b ->
+ \d1::Data a, d2::C b ->
+ \p q r -> case p of { p ->
+ case q of { q ->
+ HsCon T1 [a,b] [p,q,r]}}
+
+Notice that
+
+* d2 is thrown away --- a context in a data decl is used to make sure
+ one *could* construct dictionaries at the site the constructor
+ is used, but the dictionary isn't actually used.
+
+* We have to check that we can construct Data dictionaries for
+ the types a and Int. Once we've done that we can throw d1 away too.
+
+* We use (case p of ...) to evaluate p, rather than "seq" because
+ all that matters is that the arguments are evaluated. "seq" is
+ very careful to preserve evaluation order, which we don't need
+ to be here.
+
+\begin{code}
+mkConstructor con_id
+ | not (isLocallyDefinedName (getName con_id))
+ = returnTc (con_id, EmptyMonoBinds)
+
+ | otherwise -- It is locally defined
+ = tcInstId con_id `thenNF_Tc` \ (tc_tyvars, tc_theta, tc_tau) ->
+ newDicts DataDeclOrigin tc_theta `thenNF_Tc` \ (_, dicts) ->
+ let
+ (tc_arg_tys, tc_result_ty) = splitFunTy tc_tau
+ n_args = length tc_arg_tys
+ in
+ newLocalIds (nOfThem n_args SLIT("con")) tc_arg_tys `thenNF_Tc` \ args ->
+
+ -- Check that all the types of all the strict arguments are in Eval
+ tcLookupClassByKey evalClassKey `thenNF_Tc` \ eval_clas ->
+ let
+ (_,theta,tau) = splitSigmaTy (idType con_id)
+ (arg_tys, _) = splitFunTy tau
+ strict_marks = dataConStrictMarks con_id
+ eval_theta = [ (eval_clas,arg_ty)
+ | (arg_ty, MarkedStrict) <- zipEqual "strict_args"
+ arg_tys strict_marks
+ ]
+ in
+ tcSimplifyThetas classInstEnv theta eval_theta `thenTc` \ eval_theta' ->
+ checkTc (null eval_theta')
+ (missingEvalErr con_id eval_theta') `thenTc_`
+
+ -- Build the data constructor
+ let
+ con_rhs = mkHsTyLam tc_tyvars $
+ mkHsDictLam dicts $
+ mk_pat_match args $
+ mk_case (zipEqual "strict_args" args strict_marks) $
+ HsCon con_id (mkTyVarTys tc_tyvars) (map HsVar args)
+
+ mk_pat_match [] body = body
+ mk_pat_match (arg:args) body = HsLam $
+ PatMatch (VarPat arg) $
+ SimpleMatch (mk_pat_match args body)
+
+ mk_case [] body = body
+ mk_case ((arg,MarkedStrict):args) body = HsCase (HsVar arg)
+ [PatMatch (VarPat arg) $
+ SimpleMatch (mk_case args body)]
+ src_loc
+ mk_case (_:args) body = mk_case args body
+
+ src_loc = nameSrcLoc (getName con_id)
+ in
+
+ returnTc (con_id, VarMonoBind (RealId con_id) con_rhs)
+\end{code}
+
We're going to build a record selector that looks like this:
data T a b c = T1 { op :: a, ...}
label; it has to be an Id, you see!
\begin{code}
-tcRecordSelector tycon fields@((first_con, first_field_label) : other_fields)
- = panic "tcRecordSelector: don't typecheck"
-{-
+mkRecordSelector tycon fields@((first_con, first_field_label) : other_fields)
= let
field_ty = fieldLabelType first_field_label
field_name = fieldLabelName first_field_label
- other_tys = [fieldLabelType fl | (_, fl) <- fields]
+ other_tys = [fieldLabelType fl | (_, fl) <- other_fields]
(tyvars, _, _, _) = dataConSig first_con
- -- tyvars of first_con may be free in first_ty
+ data_ty = applyTyCon tycon (mkTyVarTys tyvars)
+ -- tyvars of first_con may be free in field_ty
in
-- Check that all the fields in the group have the same type
tcInstTyVars tyvars `thenNF_Tc` \ (tyvars', tyvar_tys, tenv) ->
tcInstType tenv field_ty `thenNF_Tc` \ field_ty' ->
let
- data_ty' = applyTyCon tycon tyvar_tys
+ data_ty' = applyTyCon tycon tyvar_tys
in
newLocalId SLIT("x") field_ty' `thenNF_Tc` \ field_id ->
newLocalId SLIT("r") data_ty' `thenNF_Tc` \ record_id ->
-- Now build the selector
let
- tycon_src_loc = getSrcLoc tycon
-
- selector_ty = mkForAllTys tyvars' $
- mkFunTy data_ty' $
- field_ty'
+ selector_ty :: Type
+ selector_ty = mkForAllTys tyvars $
+ mkFunTy data_ty $
+ field_ty
- selector_id = mkRecordSelectorId first_field_label selector_ty
+ selector_id :: Id
+ selector_id = mkRecordSelId first_field_label selector_ty
-- HsSyn is dreadfully verbose for defining the selector!
selector_rhs = mkHsTyLam tyvars' $
HsLam $
PatMatch (VarPat record_id) $
- GRHSMatch $
- GRHSsAndBindsOut [OtherwiseGRHS selector_body tycon_src_loc]
- EmptyBinds field_ty'
+ SimpleMatch $
+ selector_body
- selector_body = HsCase (HsVar record_id) (map mk_match fields) tycon_src_loc
+ selector_body = HsCase (HsVar record_id) (map mk_match fields) (getSrcLoc tycon)
mk_match (con_id, field_label)
= PatMatch (RecPat con_id data_ty' [(selector_id, VarPat field_id, False)]) $
- GRHSMatch $
- GRHSsAndBindsOut [OtherwiseGRHS (HsVar field_id)
- (getSrcLoc (fieldLabelName field_label))]
- EmptyBinds
- field_ty'
+ SimpleMatch $
+ HsVar field_id
in
- returnTc (selector_id, VarMonoBind selector_id selector_rhs)
--}
+ returnTc (selector_id, if isLocallyDefinedName (getName tycon)
+ then VarMonoBind (RealId selector_id) selector_rhs
+ else EmptyMonoBinds)
\end{code}
Constructors
= tcAddSrcLoc src_loc $
tcMonoType ty `thenTc` \ arg_ty ->
let
- data_con = mkDataCon (getItsUnique name)
- (getNameFullName name)
+ data_con = mkDataCon (getName name)
[NotMarkedStrict]
[{- No labelled fields -}]
tyvars
stricts = [strict | (_, _, strict) <- field_label_infos]
arg_tys = [ty | (_, ty, _) <- field_label_infos]
- field_labels = [ mkFieldLabel name ty tag
- | ((name, ty, _), tag) <- field_label_infos `zip` allFieldLabelTags
- ]
+ field_labels = [ mkFieldLabel (getName name) ty tag
+ | ((name, ty, _), tag) <- field_label_infos `zip` allFieldLabelTags ]
- data_con = mkDataCon (getItsUnique name)
- (getNameFullName name)
+ data_con = mkDataCon (getName name)
stricts
field_labels
tyvars
returnTc data_con
tcField (field_label_names, bty)
- = tcMonoType (get_ty bty) `thenTc` \ field_ty ->
+ = tcPolyType (get_pty bty) `thenTc` \ field_ty ->
returnTc [(name, field_ty, get_strictness bty) | name <- field_label_names]
tcDataCon tycon tyvars ctxt name btys src_loc
= tcAddSrcLoc src_loc $
let
stricts = map get_strictness btys
- tys = map get_ty btys
+ tys = map get_pty btys
in
- mapTc tcMonoType tys `thenTc` \ arg_tys ->
+ mapTc tcPolyType tys `thenTc` \ arg_tys ->
let
- data_con = mkDataCon (getItsUnique name)
- (getNameFullName name)
+ data_con = mkDataCon (getName name)
stricts
[{- No field labels -}]
tyvars
arg_tyvars = tyVarsOfTypes arg_tys
in_arg_tys (clas,ty) = getTyVar "tcDataCon" ty `elementOfTyVarSet` arg_tyvars
-get_strictness (Banged ty) = MarkedStrict
-get_strictness (Unbanged ty) = NotMarkedStrict
+get_strictness (Banged _) = MarkedStrict
+get_strictness (Unbanged _) = NotMarkedStrict
-get_ty (Banged ty) = ty
-get_ty (Unbanged ty) = ty
+get_pty (Banged ty) = ty
+get_pty (Unbanged ty) = ty
\end{code}
fieldTypeMisMatch field_name sty
= ppSep [ppStr "Declared types differ for field", ppr sty field_name]
+
+missingEvalErr con eval_theta sty
+ = ppCat [ppStr "Missing Eval context for constructor",
+ ppQuote (ppr sty con),
+ ppStr ":", ppr sty eval_theta]
\end{code}
projects / ghc-hetmet.git / blobdiff