%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1995
+% (c) The AQUA Project, Glasgow University, 1996-1998
%
-\section[TcTyDecls]{Typecheck algebraic datatypes and type synonyms}
+\section[TcTyDecls]{Typecheck type declarations}
\begin{code}
-#include "HsVersions.h"
+module TcTyDecls ( tcTyDecl, kcConDetails ) where
-module TcTyDecls ( tcTyDecls ) where
+#include "HsVersions.h"
-import TcMonad -- typechecking monad machinery
-import AbsSyn -- the stuff being typechecked
+import HsSyn ( TyClDecl(..), ConDecl(..), HsConDetails(..), BangType,
+ getBangType, getBangStrictness, conDetailsTys
+ )
+import RnHsSyn ( RenamedTyClDecl, RenamedConDecl, RenamedContext )
+import BasicTypes ( NewOrData(..) )
-import AbsUniType ( applyTyCon, mkDataTyCon, mkSynonymTyCon,
- getUniDataTyCon, isUnboxedDataType,
- isTyVarTemplateTy, cmpUniTypeMaybeList,
- pprMaybeTy
+import TcMonoType ( tcHsTyVars, tcHsTheta, tcHsType,
+ kcHsContext, kcHsSigType, kcHsLiftedSigType
)
-import CE ( lookupCE, CE(..) )
-import CmdLineOpts ( GlobalSwitch(..) )
-import E ( getE_TCE, getE_CE, plusGVE, nullGVE, GVE(..), E )
-import ErrUtils ( addShortErrLocLine )
-import Errors ( confusedNameErr, specDataNoSpecErr, specDataUnboxedErr )
-import FiniteMap ( FiniteMap, emptyFM, plusFM, singletonFM )
-import IdInfo ( SpecEnv, mkSpecEnv, SpecInfo(..) )
-import Pretty
-import SpecTyFuns ( specialiseConstrTys )
-import TCE -- ( nullTCE, unitTCE, lookupTCE, plusTCE, TCE(..), UniqFM )
-import TVE ( mkTVE, TVE(..) )
-import TcConDecls ( tcConDecls )
-import TcMonoType ( tcMonoType )
-import TcPragmas ( tcDataPragmas, tcTypePragmas )
-import Util
+import TcEnv ( tcExtendTyVarEnv, tcLookupTyCon, TyThingDetails(..) )
+import TcType ( tyVarsOfTypes, tyVarsOfPred, ThetaType )
+import RnEnv ( lookupSysName )
+import TcRnMonad
+
+import DataCon ( DataCon, mkDataCon, dataConFieldLabels )
+import FieldLabel ( fieldLabelName, fieldLabelType, allFieldLabelTags, mkFieldLabel )
+import MkId ( mkDataConId, mkDataConWrapId, mkRecordSelId )
+import Var ( TyVar )
+import Name ( Name )
+import OccName ( mkWorkerOcc, mkGenOcc1, mkGenOcc2 )
+import Outputable
+import TyCon ( TyCon, DataConDetails(..), visibleDataCons,
+ tyConTyVars, tyConName )
+import VarSet ( intersectVarSet, isEmptyVarSet )
+import Generics ( mkTyConGenInfo )
+import CmdLineOpts ( DynFlag(..) )
+import List ( nubBy )
\end{code}
-We consult the @CE@/@TCE@ arguments {\em only} to build knots!
-
-The resulting @TCE@ has info about the type constructors in it; the
-@GVE@ has info about their data constructors.
+%************************************************************************
+%* *
+\subsection{Type checking}
+%* *
+%************************************************************************
\begin{code}
-tcTyDecls :: E
- -> (Name -> Bool) -- given Name, is it an abstract synonym?
- -> (Name -> [RenamedDataTypeSig]) -- given Name, get specialisation pragmas
- -> [RenamedTyDecl]
- -> Baby_TcM (TCE, GVE,
- FiniteMap TyCon [[Maybe UniType]])
- -- specialisations:
- -- local data types: requsted by source pragmas
- -- imported data types: from interface file
-
-tcTyDecls e _ _ [] = returnB_Tc (nullTCE, nullGVE, emptyFM)
-
-tcTyDecls e is_abs_syn get_spec_sigs (tyd: tyds)
- = tc_decl tyd `thenB_Tc` \ (tce1, gve1, specs1) ->
- tcTyDecls e is_abs_syn get_spec_sigs tyds
- `thenB_Tc` \ (tce2, gve2, specs2) ->
+tcTyDecl :: RenamedTyClDecl -> TcM (Name, TyThingDetails)
+tcTyDecl (TySynonym {tcdName = tycon_name, tcdSynRhs = rhs})
+ = tcLookupTyCon tycon_name `thenM` \ tycon ->
+ tcExtendTyVarEnv (tyConTyVars tycon) $
+ tcHsType rhs `thenM` \ rhs_ty ->
+ returnM (tycon_name, SynTyDetails rhs_ty)
+
+tcTyDecl (TyData {tcdND = new_or_data, tcdCtxt = context,
+ tcdName = tycon_name, tcdCons = con_decls,
+ tcdGeneric = generic})
+ = tcLookupTyCon tycon_name `thenM` \ tycon ->
let
- tce3 = tce1 `plusTCE` tce2
- gve3 = gve1 `plusGVE` gve2
- specs3 = specs1 `plusFM` specs2
+ tyvars = tyConTyVars tycon
in
- returnB_Tc (tce3, gve3, specs3)
- where
- rec_ce = getE_CE e
- rec_tce = getE_TCE e
-
- -- continued...
-\end{code}
-
-We don't need to substitute here, because the @TCE@s
-(which are at the top level) cannot contain free type variables.
-
-Gather relevant info:
-\begin{code}
- tc_decl (TyData context name@(PreludeTyCon uniq full_name arity True{-"data"-})
- tyvars con_decls derivings pragmas src_loc)
- -- ToDo: context
- = tc_data_decl uniq name full_name arity tyvars con_decls
- derivings pragmas src_loc
-
- tc_decl (TyData context name@(OtherTyCon uniq full_name arity True{-"data"-} _)
- tyvars con_decls derivings pragmas src_loc)
- -- ToDo: context
- = tc_data_decl uniq name full_name arity tyvars con_decls
- derivings pragmas src_loc
-
- tc_decl (TyData _ bad_name _ _ _ _ src_loc)
- = failB_Tc (confusedNameErr "Bad name on a datatype constructor (a Prelude name?)"
- bad_name src_loc)
-
- tc_decl (TySynonym name@(PreludeTyCon uniq full_name arity False{-"type"-})
- tyvars mono_ty pragmas src_loc)
- = tc_syn_decl uniq name full_name arity tyvars mono_ty pragmas src_loc
-
- tc_decl (TySynonym name@(OtherTyCon uniq full_name arity False{-"type"-} _)
- tyvars mono_ty pragmas src_loc)
- = tc_syn_decl uniq name full_name arity tyvars mono_ty pragmas src_loc
-
- tc_decl (TySynonym bad_name _ _ _ src_loc)
- = failB_Tc (confusedNameErr "Bad name on a type-synonym constructor (a Prelude name?)"
- bad_name src_loc)
-\end{code}
-
-Real work for @data@ declarations:
-\begin{code}
- tc_data_decl uniq name full_name arity tyvars con_decls derivings pragmas src_loc
- = addSrcLocB_Tc src_loc (
- let
- (tve, new_tyvars, _) = mkTVE tyvars
- rec_tycon = lookupTCE rec_tce name
- -- We know the lookup will succeed, because we are just
- -- about to put it in the outgoing TCE!
-
- spec_sigs = get_spec_sigs name
- in
- tcSpecDataSigs rec_tce spec_sigs [] `thenB_Tc` \ user_spec_infos ->
-
- recoverIgnoreErrorsB_Tc ([], []) (
- tcDataPragmas rec_tce tve rec_tycon new_tyvars pragmas
- ) `thenB_Tc` \ (pragma_con_decls, pragma_spec_infos) ->
- let
- (condecls_to_use, ignore_condecl_errors_if_pragma)
- = if null pragma_con_decls then
- (con_decls, id)
- else
- if null con_decls
- then (pragma_con_decls, recoverIgnoreErrorsB_Tc nullGVE)
- else panic "tcTyDecls:data: user and pragma condecls!"
-
- specinfos_to_use
- = if null pragma_spec_infos then
- user_spec_infos
- else
- if null user_spec_infos
- then pragma_spec_infos
- else panic "tcTyDecls:data: user and pragma specinfos!"
-
- specenv_to_use = mkSpecEnv specinfos_to_use
- in
- ignore_condecl_errors_if_pragma
- (tcConDecls rec_tce tve rec_tycon new_tyvars specenv_to_use condecls_to_use)
- `thenB_Tc` \ gve ->
- let
- condecls = map snd gve
-
- derived_classes = map (lookupCE rec_ce) derivings
+ tcExtendTyVarEnv tyvars $
+ tcHsTheta context `thenM` \ ctxt ->
+ tcConDecls new_or_data tycon tyvars ctxt con_decls `thenM` \ data_cons ->
+ let
+ sel_ids = mkRecordSelectors tycon data_cons
+ in
+ tcGenericInfo tycon generic `thenM` \ gen_info ->
+ returnM (tycon_name, DataTyDetails ctxt data_cons sel_ids gen_info)
- new_tycon
- = mkDataTyCon uniq
- full_name arity new_tyvars condecls
- derived_classes
- (null pragma_con_decls)
- -- if constrs are from pragma we are *abstract*
+tcTyDecl (ForeignType {tcdName = tycon_name})
+ = returnM (tycon_name, ForeignTyDetails)
- spec_list
- = map (\ (SpecInfo maybe_tys _ _) -> maybe_tys) specinfos_to_use
- spec_map
- = if null spec_list then
- emptyFM
- else
- singletonFM rec_tycon spec_list
- in
- returnB_Tc (unitTCE uniq new_tycon, gve, spec_map)
- -- It's OK to return pragma condecls in gve, even
- -- though some of those names should be "invisible",
- -- because the *renamer* is supposed to have dealt with
- -- naming/scope issues already.
- )
+tcGenericInfo tycon generics -- Source code decl: consult the flag
+ = do_we_want generics `thenM` \ want_generics ->
+ if want_generics then
+ mapM (lookupSysName (tyConName tycon))
+ [mkGenOcc1, mkGenOcc2] `thenM` \ gen_sys_names ->
+ returnM (mkTyConGenInfo tycon gen_sys_names)
+ else
+ returnM Nothing
+ where
+ do_we_want (Just g) = returnM g -- Interface file decl
+ -- so look at decl
+ do_we_want Nothing = doptM Opt_Generics -- Source code decl
+ -- so look at flag
+
+mkRecordSelectors tycon data_cons
+ = -- We'll check later that fields with the same name
+ -- from different constructors have the same type.
+ [ mkRecordSelId tycon field
+ | field <- nubBy eq_name fields ]
+ where
+ fields = [ field | con <- visibleDataCons data_cons,
+ field <- dataConFieldLabels con ]
+ eq_name field1 field2 = fieldLabelName field1 == fieldLabelName field2
\end{code}
-Real work for @type@ (synonym) declarations:
-\begin{code}
- tc_syn_decl uniq name full_name arity tyvars mono_ty pragmas src_loc
- = addSrcLocB_Tc src_loc (
-
- let (tve, new_tyvars, _) = mkTVE tyvars
- in
- tcMonoType rec_ce rec_tce tve mono_ty `thenB_Tc` \ expansion ->
- let
- -- abstractness info either comes from the interface pragmas
- -- (tcTypePragmas) or from a user-pragma in this module
- -- (is_abs_syn)
- abstract = tcTypePragmas pragmas
- || is_abs_syn name
-
- new_tycon = mkSynonymTyCon uniq full_name
- arity new_tyvars expansion (not abstract)
- in
- returnB_Tc (unitTCE uniq new_tycon, nullGVE, emptyFM)
- )
-\end{code}
%************************************************************************
%* *
-\subsection{Specialisation Signatures for Data Type declarations}
+\subsection{Kind and type check constructors}
%* *
%************************************************************************
-@tcSpecDataSigs@ checks data type specialisation signatures for
-validity, and returns the list of specialisation requests.
-
\begin{code}
-tcSpecDataSigs :: TCE
- -> [RenamedDataTypeSig]
- -> [(RenamedDataTypeSig,SpecInfo)]
- -> Baby_TcM [SpecInfo]
-
-tcSpecDataSigs tce (s:ss) accum
- = tc_sig s `thenB_Tc` \ info ->
- tcSpecDataSigs tce ss ((s,info):accum)
+kcConDetails :: NewOrData -> RenamedContext
+ -> HsConDetails Name (BangType Name) -> TcM ()
+kcConDetails new_or_data ex_ctxt details
+ = kcHsContext ex_ctxt `thenM_`
+ mappM_ kc_sig_type (conDetailsTys details)
where
- tc_sig (SpecDataSig n ty src_loc)
- = addSrcLocB_Tc src_loc (
- let
- ty_names = extractMonoTyNames (==) ty
- (tve,_,_) = mkTVE ty_names
- fake_CE = panic "tcSpecDataSigs:CE"
- in
- -- Typecheck specialising type (includes arity check)
- tcMonoType fake_CE tce tve ty `thenB_Tc` \ tau_ty ->
- let
- (_,ty_args,_) = getUniDataTyCon tau_ty
- is_unboxed_or_tyvar ty = isUnboxedDataType ty || isTyVarTemplateTy ty
- in
- -- Check at least one unboxed type in specialisation
- checkB_Tc (not (any isUnboxedDataType ty_args))
- (specDataNoSpecErr n ty_args src_loc) `thenB_Tc_`
-
- -- Check all types are unboxed or tyvars
- -- (specific boxed types are redundant)
- checkB_Tc (not (all is_unboxed_or_tyvar ty_args))
- (specDataUnboxedErr n ty_args src_loc) `thenB_Tc_`
-
- let
- maybe_tys = specialiseConstrTys ty_args
- in
- returnB_Tc (SpecInfo maybe_tys 0 (panic "SpecData:SpecInfo:SpecId"))
- )
-
-tcSpecDataSigs tce [] accum
- = -- Remove any duplicates from accumulated specinfos
- getSwitchCheckerB_Tc `thenB_Tc` \ sw_chkr ->
+ kc_sig_type = case new_or_data of
+ DataType -> kcHsSigType
+ NewType -> kcHsLiftedSigType
+ -- Can't allow an unlifted type here, because we're effectively
+ -- going to remove the constructor while coercing it to a lifted type.
+
+
+tcConDecls :: NewOrData -> TyCon -> [TyVar] -> ThetaType
+ -> DataConDetails RenamedConDecl -> TcM (DataConDetails DataCon)
+
+tcConDecls new_or_data tycon tyvars ctxt con_decls
+ = case con_decls of
+ Unknown -> returnM Unknown
+ HasCons n -> returnM (HasCons n)
+ DataCons cs -> mappM tc_con_decl cs `thenM` \ data_cons ->
+ returnM (DataCons data_cons)
+ where
+ tc_con_decl (ConDecl name ex_tvs ex_ctxt details src_loc)
+ = addSrcLoc src_loc $
+ tcHsTyVars ex_tvs (kcConDetails new_or_data ex_ctxt details) $ \ ex_tyvars ->
+ tcHsTheta ex_ctxt `thenM` \ ex_theta ->
+ case details of
+ PrefixCon btys -> tc_datacon ex_tyvars ex_theta btys
+ InfixCon bty1 bty2 -> tc_datacon ex_tyvars ex_theta [bty1,bty2]
+ RecCon fields -> tc_rec_con ex_tyvars ex_theta fields
+ where
+
+ tc_datacon ex_tyvars ex_theta btys
+ = mappM tcHsType (map getBangType btys) `thenM` \ arg_tys ->
+ mk_data_con ex_tyvars ex_theta (map getBangStrictness btys) arg_tys []
- (if sw_chkr SpecialiseTrace && not (null duplicates) then
- pprTrace "Duplicate SPECIALIZE data pragmas:\n"
- (ppAboves (map specmsg sep_dups))
- else id)(
-
- (if sw_chkr SpecialiseTrace && not (null spec_infos) then
- pprTrace "Specialising "
- (ppHang (ppCat [ppr PprDebug name, ppStr "at types:"])
- 4 (ppAboves (map pp_spec spec_infos)))
-
- else id) (
-
- returnB_Tc (spec_infos)
- ))
+ tc_rec_con ex_tyvars ex_theta fields
+ = checkTc (null ex_tyvars) (exRecConErr name) `thenM_`
+ mappM tc_field (fields `zip` allFieldLabelTags) `thenM` \ field_labels ->
+ let
+ arg_stricts = [str | (n, bty) <- fields,
+ let str = getBangStrictness bty
+ ]
+ in
+ mk_data_con ex_tyvars ex_theta arg_stricts
+ (map fieldLabelType field_labels) field_labels
+
+ tc_field ((field_label_name, bty), tag)
+ = tcHsType (getBangType bty) `thenM` \ field_ty ->
+ returnM (mkFieldLabel field_label_name tycon field_ty tag)
+
+ mk_data_con ex_tyvars ex_theta arg_stricts arg_tys fields
+ = lookupSysName name mkWorkerOcc `thenM` \ wkr_name ->
+ let
+ data_con = mkDataCon name arg_stricts fields
+ tyvars (thinContext arg_tys ctxt)
+ ex_tyvars ex_theta
+ arg_tys
+ tycon data_con_id data_con_wrap_id
+
+ data_con_id = mkDataConId wkr_name data_con
+ data_con_wrap_id = mkDataConWrapId data_con
+ in
+ returnM data_con
+
+-- The context for a data constructor should be limited to
+-- the type variables mentioned in the arg_tys
+thinContext arg_tys ctxt
+ = filter in_arg_tys ctxt
where
- spec_infos = map (snd . head) equiv
-
- equiv = equivClasses cmp_info accum
- duplicates = filter (not . singleton) equiv
+ arg_tyvars = tyVarsOfTypes arg_tys
+ in_arg_tys pred = not $ isEmptyVarSet $
+ tyVarsOfPred pred `intersectVarSet` arg_tyvars
+\end{code}
- cmp_info (_, SpecInfo tys1 _ _) (_, SpecInfo tys2 _ _)
- = cmpUniTypeMaybeList tys1 tys2
- singleton [_] = True
- singleton _ = False
+%************************************************************************
+%* *
+\subsection{Errors and contexts}
+%* *
+%************************************************************************
- sep_dups = tail (concat (map ((:) Nothing . map Just) duplicates))
- specmsg (Just (SpecDataSig _ ty locn, _))
- = addShortErrLocLine locn ( \ sty -> ppr sty ty ) PprDebug
- specmsg Nothing
- = ppStr "***"
- ((SpecDataSig name _ _, _):_) = accum
- pp_spec (SpecInfo tys _ _) = ppInterleave ppNil [pprMaybeTy PprDebug ty | ty <- tys]
+\begin{code}
+exRecConErr name
+ = ptext SLIT("Can't combine named fields with locally-quantified type variables")
+ $$
+ (ptext SLIT("In the declaration of data constructor") <+> ppr name)
\end{code}