\section[TcTyDecls]{Typecheck type declarations}
\begin{code}
-module TcTyDecls ( tcTyDecl, checkValidTyCon, kcConDetails ) where
+module TcTyDecls ( tcTyDecl, kcConDetails ) where
#include "HsVersions.h"
TyThingDetails(..), RecTcEnv
)
import TcType ( tcEqType, tyVarsOfTypes, tyVarsOfPred, ThetaType )
-import TcMType ( checkValidType, UserTypeCtxt(..), checkValidTheta, SourceTyCtxt(..) )
import TcMonad
-import DataCon ( DataCon, mkDataCon, dataConFieldLabels, dataConWrapId, dataConName )
+import DataCon ( DataCon, mkDataCon, dataConFieldLabels )
+import FieldLabel ( fieldLabelName, fieldLabelType, allFieldLabelTags, mkFieldLabel )
import MkId ( mkDataConId, mkDataConWrapId, mkRecordSelId )
-import FieldLabel
-import Var ( TyVar, idType )
+import Var ( TyVar )
import Name ( Name, NamedThing(..) )
import Outputable
-import TyCon ( TyCon, tyConName, tyConTheta, getSynTyConDefn, tyConTyVars, tyConDataCons, isSynTyCon )
+import TyCon ( TyCon, DataConDetails(..), visibleDataCons,
+ tyConName, tyConTheta,
+ tyConTyVars, isSynTyCon )
import VarSet ( intersectVarSet, isEmptyVarSet )
import PrelNames ( unpackCStringName, unpackCStringUtf8Name )
-import ListSetOps ( equivClasses )
import List ( nubBy )
\end{code}
returnTc (tycon_name, SynTyDetails rhs_ty)
tcTyDecl unf_env (TyData {tcdND = new_or_data, tcdCtxt = context,
- tcdName = tycon_name, tcdCons = con_decls})
+ tcdName = tycon_name, tcdCons = con_decls})
= tcLookupTyCon tycon_name `thenNF_Tc` \ tycon ->
let
tyvars = tyConTyVars tycon
in
tcExtendTyVarEnv tyvars $
- tcHsTheta context `thenTc` \ ctxt ->
- mapTc (tcConDecl new_or_data tycon tyvars ctxt) con_decls `thenTc` \ data_cons ->
+ tcHsTheta context `thenTc` \ ctxt ->
+ tcConDecls new_or_data tycon tyvars ctxt con_decls `thenTc` \ data_cons ->
let
sel_ids = mkRecordSelectors unf_env tycon data_cons
in
[ mkRecordSelId tycon field unpack_id unpackUtf8_id
| field <- nubBy eq_name fields ]
where
- fields = [ field | con <- data_cons, field <- dataConFieldLabels con ]
+ fields = [ field | con <- visibleDataCons data_cons,
+ field <- dataConFieldLabels con ]
eq_name field1 field2 = fieldLabelName field1 == fieldLabelName field2
unpack_id = tcLookupRecId unf_env unpackCStringName
%************************************************************************
%* *
-\subsection{Validity check}
-%* *
-%************************************************************************
-
-checkValidTyCon is called once the mutually-recursive knot has been
-tied, so we can look at things freely.
-
-\begin{code}
-checkValidTyCon :: TyCon -> TcM ()
-checkValidTyCon tc
- | isSynTyCon tc = checkValidType (TySynCtxt name) syn_rhs
- | otherwise
- = -- Check the context on the data decl
- checkValidTheta (DataTyCtxt name) (tyConTheta tc) `thenTc_`
-
- -- Check arg types of data constructors
- mapTc_ check_data_con data_cons `thenTc_`
-
- -- Check that fields with the same name share a type
- mapTc_ check_fields groups
-
- where
- name = tyConName tc
- (_, syn_rhs) = getSynTyConDefn tc
- data_cons = tyConDataCons tc
-
- fields = [field | con <- data_cons, field <- dataConFieldLabels con]
- groups = equivClasses cmp_name fields
- cmp_name field1 field2 = fieldLabelName field1 `compare` fieldLabelName field2
-
- check_data_con con = checkValidType (ConArgCtxt (dataConName con))
- (idType (dataConWrapId con))
- -- This checks the argument types and
- -- the existential context (if any)
-
- check_fields fields@(first_field_label : other_fields)
- -- These fields all have the same name, but are from
- -- different constructors in the data type
- = -- Check that all the fields in the group have the same type
- -- NB: this check assumes that all the constructors of a given
- -- data type use the same type variables
- checkTc (all (tcEqType field_ty) other_tys) (fieldTypeMisMatch field_name)
- where
- field_ty = fieldLabelType first_field_label
- field_name = fieldLabelName first_field_label
- other_tys = map fieldLabelType other_fields
-\end{code}
-
-
-
-%************************************************************************
-%* *
\subsection{Kind and type check constructors}
%* *
%************************************************************************
-- going to remove the constructor while coercing it to a lifted type.
-tcConDecl :: NewOrData -> TyCon -> [TyVar] -> ThetaType -> RenamedConDecl -> TcM DataCon
-tcConDecl new_or_data tycon tyvars ctxt (ConDecl name wkr_name ex_tvs ex_ctxt details src_loc)
- = tcAddSrcLoc src_loc $
- tcHsTyVars ex_tvs (kcConDetails new_or_data ex_ctxt details) $ \ ex_tyvars ->
- tcHsTheta ex_ctxt `thenTc` \ ex_theta ->
- case details of
- VanillaCon 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
+tcConDecls :: NewOrData -> TyCon -> [TyVar] -> ThetaType
+ -> DataConDetails RenamedConDecl -> TcM (DataConDetails DataCon)
+
+tcConDecls new_or_data tycon tyvars ctxt con_decls
+ = case con_decls of
+ Unknown -> returnTc Unknown
+ HasCons n -> returnTc (HasCons n)
+ DataCons cs -> mapTc tc_con_decl cs `thenTc` \ data_cons ->
+ returnTc (DataCons data_cons)
where
- tc_datacon ex_tyvars ex_theta btys
- = mapTc tcHsType (map getBangType btys) `thenTc` \ arg_tys ->
- mk_data_con ex_tyvars ex_theta (map getBangStrictness btys) arg_tys []
-
- tc_rec_con ex_tyvars ex_theta fields
- = checkTc (null ex_tyvars) (exRecConErr name) `thenTc_`
- mapTc tc_field (fields `zip` allFieldLabelTags) `thenTc` \ field_labels_s ->
- let
- field_labels = concat field_labels_s
- arg_stricts = [str | (ns, bty) <- fields,
- let str = getBangStrictness bty,
- n <- ns -- One for each. E.g x,y,z :: !Int
- ]
- in
- mk_data_con ex_tyvars ex_theta arg_stricts
- (map fieldLabelType field_labels) field_labels
-
- tc_field ((field_label_names, bty), tag)
- = tcHsType (getBangType bty) `thenTc` \ field_ty ->
- returnTc [mkFieldLabel (getName name) tycon field_ty tag | name <- field_label_names]
-
- mk_data_con ex_tyvars ex_theta arg_stricts arg_tys fields
- = 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
- returnNF_Tc data_con
+ tc_con_decl (ConDecl name wkr_name ex_tvs ex_ctxt details src_loc)
+ = tcAddSrcLoc src_loc $
+ tcHsTyVars ex_tvs (kcConDetails new_or_data ex_ctxt details) $ \ ex_tyvars ->
+ tcHsTheta ex_ctxt `thenTc` \ ex_theta ->
+ case details of
+ VanillaCon 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
+ = mapTc tcHsType (map getBangType btys) `thenTc` \ arg_tys ->
+ mk_data_con ex_tyvars ex_theta (map getBangStrictness btys) arg_tys []
+
+ tc_rec_con ex_tyvars ex_theta fields
+ = checkTc (null ex_tyvars) (exRecConErr name) `thenTc_`
+ mapTc tc_field (fields `zip` allFieldLabelTags) `thenTc` \ field_labels_s ->
+ let
+ field_labels = concat field_labels_s
+ arg_stricts = [str | (ns, bty) <- fields,
+ let str = getBangStrictness bty,
+ n <- ns -- One for each. E.g x,y,z :: !Int
+ ]
+ in
+ mk_data_con ex_tyvars ex_theta arg_stricts
+ (map fieldLabelType field_labels) field_labels
+
+ tc_field ((field_label_names, bty), tag)
+ = tcHsType (getBangType bty) `thenTc` \ field_ty ->
+ returnTc [mkFieldLabel (getName name) tycon field_ty tag | name <- field_label_names]
+
+ mk_data_con ex_tyvars ex_theta arg_stricts arg_tys fields
+ = 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
+ returnNF_Tc data_con
-- The context for a data constructor should be limited to
-- the type variables mentioned in the arg_tys
\begin{code}
-fieldTypeMisMatch field_name
- = sep [ptext SLIT("Different constructors give different types for field"), quotes (ppr field_name)]
-
exRecConErr name
= ptext SLIT("Can't combine named fields with locally-quantified type variables")
$$
projects / ghc-hetmet.git / blobdiff