\begin{code}
#include "HsVersions.h"
-module TcClassDcl (
- tcClassDecl1, tcClassDecls2
- ) where
+module TcClassDcl ( tcClassDecl1, tcClassDecls2 ) where
IMP_Ubiq()
-import HsSyn ( ClassDecl(..), HsBinds(..), Bind(..), MonoBinds(..),
- Match(..), GRHSsAndBinds(..), GRHS(..), HsExpr(..),
- HsLit(..), OutPat(..), Sig(..), PolyType(..), MonoType,
- Stmt, Qualifier, ArithSeqInfo, InPat, Fake )
+import HsSyn ( HsDecl(..), ClassDecl(..), HsBinds(..), MonoBinds(..),
+ Match(..), GRHSsAndBinds(..), GRHS(..), HsExpr(..),
+ DefaultDecl, TyDecl, InstDecl, IfaceSig, Fixity,
+ HsLit(..), OutPat(..), Sig(..), HsType(..), HsTyVar,
+ SYN_IE(RecFlag), nonRecursive, andMonoBinds,
+ Stmt, DoOrListComp, ArithSeqInfo, InPat, Fake )
+import HsTypes ( getTyVarName )
import HsPragmas ( ClassPragmas(..) )
import RnHsSyn ( RenamedClassDecl(..), RenamedClassPragmas(..),
- RenamedClassOpSig(..), RenamedMonoBinds(..),
- RenamedGenPragmas(..), RenamedContext(..),
- RnName{-instance Uniquable-}
+ RenamedClassOpSig(..), SYN_IE(RenamedMonoBinds),
+ RenamedGenPragmas(..), RenamedContext(..), SYN_IE(RenamedHsDecl)
)
-import TcHsSyn ( TcIdOcc(..), TcHsBinds(..), TcMonoBinds(..), TcExpr(..),
+import TcHsSyn ( TcIdOcc(..), SYN_IE(TcHsBinds), SYN_IE(TcMonoBinds), SYN_IE(TcExpr),
mkHsTyApp, mkHsTyLam, mkHsDictApp, mkHsDictLam, tcIdType )
-import Inst ( Inst, InstOrigin(..), LIE(..), emptyLIE, plusLIE, newDicts )
-import TcEnv ( tcLookupClass, tcLookupTyVar, tcLookupTyCon, newLocalIds)
-import TcInstDcls ( processInstBinds, newMethodId )
-import TcKind ( TcKind )
-import TcKind ( unifyKind )
-import TcMonad hiding ( rnMtoTcM )
-import TcMonoType ( tcPolyType, tcMonoType, tcContext )
+import Inst ( Inst, InstOrigin(..), SYN_IE(LIE), emptyLIE, plusLIE, newDicts, newMethod )
+import TcEnv ( tcLookupClass, tcLookupTyVar, tcLookupTyCon, newLocalIds, tcAddImportedIdInfo,
+ tcExtendGlobalTyVars )
+import TcInstDcls ( tcMethodBind )
+import TcKind ( unifyKind, TcKind )
+import TcMonad
+import TcMonoType ( tcHsType, tcContext )
import TcSimplify ( tcSimplifyAndCheck )
-import TcType ( TcType(..), TcTyVar(..), tcInstType, tcInstSigTyVars, tcInstSigType )
+import TcType ( SYN_IE(TcType), SYN_IE(TcTyVar), tcInstType, tcInstSigTyVars, tcInstSigType )
import Bag ( foldBag, unionManyBags )
-import Class ( GenClass, mkClass, mkClassOp, classBigSig,
- classOps, classOpString, classOpLocalType,
- classOpTagByString
+import Class ( GenClass, GenClassOp, mkClass, mkClassOp, classBigSig,
+ classOps, classOpString, classOpLocalType, classDefaultMethodId,
+ classOpTagByOccName, SYN_IE(ClassOp), SYN_IE(Class)
)
-import Id ( mkSuperDictSelId, mkMethodSelId, mkDefaultMethodId,
- idType )
-import IdInfo ( noIdInfo )
-import Name ( isLocallyDefined, origName, getLocalName )
+import Id ( GenId, mkSuperDictSelId, mkMethodSelId,
+ mkDefaultMethodId, getIdUnfolding,
+ idType, SYN_IE(Id)
+ )
+import CoreUnfold ( getUnfoldingTemplate )
+import IdInfo
+import Name ( Name, isLocallyDefined, moduleString,
+ modAndOcc, nameString, NamedThing(..) )
+import Outputable
import PrelVals ( nO_DEFAULT_METHOD_ERROR_ID )
import PprStyle
import Pretty
-import PprType ( GenType, GenTyVar, GenClassOp )
-import SpecEnv ( SpecEnv(..) )
+import PprType ( GenClass, GenType, GenTyVar, GenClassOp )
+import SpecEnv ( SpecEnv )
import SrcLoc ( mkGeneratedSrcLoc )
import Type ( mkFunTy, mkTyVarTy, mkTyVarTys, mkDictTy,
- mkForAllTy, mkSigmaTy, splitSigmaTy)
+ mkForAllTy, mkSigmaTy, splitSigmaTy, SYN_IE(Type)
+ )
import TysWiredIn ( stringTy )
-import TyVar ( mkTyVarSet, GenTyVar )
-import Unique ( Unique )
+import TyVar ( unitTyVarSet, GenTyVar, SYN_IE(TyVar) )
+import Unique ( Unique )
+import UniqFM ( Uniquable(..) )
import Util
-- import TcPragmas ( tcGenPragmas, tcClassOpPragmas )
tcGenPragmas ty id ps = returnNF_Tc noIdInfo
-tcClassOpPragmas ty sel def spec ps = returnNF_Tc (noIdInfo, noIdInfo)
+tcClassOpPragmas ty sel def spec ps = returnNF_Tc (noIdInfo `addSpecInfo` spec,
+ noIdInfo)
\end{code}
tcAddErrCtxt (classDeclCtxt class_name) $
-- LOOK THINGS UP IN THE ENVIRONMENT
- tcLookupClass class_name `thenNF_Tc` \ (class_kind, rec_class) ->
- tcLookupTyVar tyvar_name `thenNF_Tc` \ (tyvar_kind, rec_tyvar) ->
+ tcLookupClass class_name `thenTc` \ (class_kind, rec_class) ->
+ tcLookupTyVar (getTyVarName tyvar_name) `thenNF_Tc` \ (tyvar_kind, rec_tyvar) ->
let
(rec_class_inst_env, rec_class_op_inst_fn) = rec_inst_mapper rec_class
in
in
-- Make super-class selector ids
- mapTc (mk_super_id rec_class)
- (super_classes `zip` maybe_pragmas) `thenTc` \ sc_sel_ids ->
- -- NB: we worry about matching list lengths below
+ mapTc (mk_super_id rec_class) super_classes `thenTc` \ sc_sel_ids ->
-- Done
returnTc (super_classes, sc_sel_ids)
where
- mk_super_id rec_class (super_class, maybe_pragma)
- = fixTc ( \ rec_super_id ->
- tcGetUnique `thenNF_Tc` \ uniq ->
-
- -- GET THE PRAGMA INFO FOR THE SUPERCLASS
- (case maybe_pragma of
- Nothing -> returnNF_Tc noIdInfo
- Just prag -> tcGenPragmas Nothing{-ty unknown-} rec_super_id prag
- ) `thenNF_Tc` \ id_info ->
- let
- rec_tyvar_ty = mkTyVarTy rec_tyvar
+ rec_tyvar_ty = mkTyVarTy rec_tyvar
+
+ mk_super_id rec_class super_class
+ = tcGetUnique `thenNF_Tc` \ uniq ->
+ let
ty = mkForAllTy rec_tyvar $
mkFunTy (mkDictTy rec_class rec_tyvar_ty)
(mkDictTy super_class rec_tyvar_ty)
- in
- -- BUILD THE SUPERCLASS ID
- returnTc (mkSuperDictSelId uniq rec_class super_class ty id_info)
- )
-
- maybe_pragmas :: [Maybe RenamedGenPragmas]
- maybe_pragmas = case pragmas of
- NoClassPragmas -> repeat Nothing
- SuperDictPragmas prags -> ASSERT(length prags == length context)
- map Just prags
- -- If there are any pragmas there should
- -- be one for each superclass
-
+ in
+ returnTc (mkSuperDictSelId uniq rec_class super_class ty)
tcClassSig :: Class -- Knot tying only!
Id) -- default-method ids
tcClassSig rec_clas rec_clas_tyvar rec_classop_spec_fn
- (ClassOpSig op_name
+ (ClassOpSig op_name dm_name
op_ty
- pragmas src_loc)
+ src_loc)
= tcAddSrcLoc src_loc $
fixTc ( \ ~(_, rec_sel_id, rec_defm_id) -> -- Knot for pragmas
-- NB: Renamer checks that the class type variable is mentioned in local_ty,
-- and that it is not constrained by theta
- tcPolyType op_ty `thenTc` \ local_ty ->
+ tcHsType op_ty `thenTc` \ local_ty ->
let
global_ty = mkSigmaTy [rec_clas_tyvar]
[(rec_clas, mkTyVarTy rec_clas_tyvar)]
local_ty
- class_op_nm = getLocalName op_name
+ class_op_nm = getOccName op_name
class_op = mkClassOp class_op_nm
- (classOpTagByString rec_clas{-yeeps!-} class_op_nm)
+ (classOpTagByOccName rec_clas{-yeeps!-} class_op_nm)
local_ty
in
- -- Munch the pragmas
- tcClassOpPragmas
- global_ty
- rec_sel_id rec_defm_id
- (rec_classop_spec_fn class_op)
- pragmas `thenNF_Tc` \ (op_info, defm_info) ->
-
-- Build the selector id and default method id
- tcGetUnique `thenNF_Tc` \ d_uniq ->
let
- op_uniq = uniqueOf op_name
- sel_id = mkMethodSelId op_uniq rec_clas class_op global_ty op_info
- defm_id = mkDefaultMethodId d_uniq rec_clas class_op False global_ty defm_info
+ sel_id = mkMethodSelId op_name rec_clas class_op global_ty
+ defm_id = mkDefaultMethodId dm_name rec_clas class_op False global_ty
-- ToDo: improve the "False"
in
- returnTc (class_op, sel_id, defm_id)
+ tcAddImportedIdInfo defm_id `thenNF_Tc` \ final_defm_id ->
+ returnTc (class_op, sel_id, final_defm_id)
)
\end{code}
each local class decl.
\begin{code}
-tcClassDecls2 :: Bag RenamedClassDecl
+tcClassDecls2 :: [RenamedHsDecl]
-> NF_TcM s (LIE s, TcHsBinds s)
tcClassDecls2 decls
- = foldBag combine
- tcClassDecl2
- (returnNF_Tc (emptyLIE, EmptyBinds))
- decls
+ = foldr combine
+ (returnNF_Tc (emptyLIE, EmptyBinds))
+ [tcClassDecl2 cls_decl | ClD cls_decl <- decls]
where
combine tc1 tc2 = tc1 `thenNF_Tc` \ (lie1, binds1) ->
tc2 `thenNF_Tc` \ (lie2, binds2) ->
tcAddSrcLoc src_loc $
-- Get the relevant class
- tcLookupClass class_name `thenNF_Tc` \ (_, clas) ->
+ tcLookupClass class_name `thenTc` \ (_, clas) ->
let
(tyvar, scs, sc_sel_ids, ops, op_sel_ids, defm_ids)
= classBigSig clas
- in
- tcInstSigTyVars [tyvar] `thenNF_Tc` \ ([clas_tyvar], _, _) ->
- -- Generate bindings for the selector functions
- buildSelectors clas tyvar clas_tyvar scs sc_sel_ids ops op_sel_ids
- `thenNF_Tc` \ sel_binds ->
- -- Ditto for the methods
- buildDefaultMethodBinds clas clas_tyvar defm_ids default_binds
- `thenTc` \ (const_insts, meth_binds) ->
-
- returnTc (const_insts, sel_binds `ThenBinds` meth_binds)
-\end{code}
-
-%************************************************************************
-%* *
-\subsection[ClassDcl-bld-sels]{Building the selector functions for methods and superclasses}
-%* *
-%************************************************************************
+ -- The selector binds are already in the selector Id's unfoldings
+ sel_binds = [ CoreMonoBind (RealId sel_id) (getUnfoldingTemplate (getIdUnfolding sel_id))
+ | sel_id <- sc_sel_ids ++ op_sel_ids,
+ isLocallyDefined sel_id
+ ]
-\begin{code}
-buildSelectors :: Class -- The class object
- -> TyVar -- Class type variable
- -> TcTyVar s -- Instantiated class type variable (TyVarTy)
- -> [Class] -> [Id] -- Superclasses and selectors
- -> [ClassOp] -> [Id] -- Class ops and selectors
- -> NF_TcM s (TcHsBinds s)
-
-buildSelectors clas clas_tyvar clas_tc_tyvar scs sc_sel_ids ops op_sel_ids
- =
- -- Make new Ids for the components of the dictionary
- let
- clas_tyvar_ty = mkTyVarTy clas_tc_tyvar
- mk_op_ty = tcInstType [(clas_tyvar, clas_tyvar_ty)] . classOpLocalType
- in
- mapNF_Tc mk_op_ty ops `thenNF_Tc` \ op_tys ->
- newLocalIds (map classOpString ops) op_tys `thenNF_Tc` \ method_ids ->
-
- newDicts ClassDeclOrigin
- [ (super_clas, clas_tyvar_ty)
- | super_clas <- scs ] `thenNF_Tc` \ (_,dict_ids) ->
-
- newDicts ClassDeclOrigin
- [ (clas, clas_tyvar_ty) ] `thenNF_Tc` \ (_,[clas_dict]) ->
-
- -- Make suitable bindings for the selectors
- let
- mk_sel sel_id method_or_dict
- = mkSelBind sel_id clas_tc_tyvar clas_dict dict_ids method_ids method_or_dict
+ final_sel_binds = MonoBind (andMonoBinds sel_binds) [] nonRecursive
in
- listNF_Tc (zipWithEqual "mk_sel1" mk_sel op_sel_ids method_ids) `thenNF_Tc` \ op_sel_binds ->
- listNF_Tc (zipWithEqual "mk_sel2" mk_sel sc_sel_ids dict_ids) `thenNF_Tc` \ sc_sel_binds ->
-
- returnNF_Tc (SingleBind (
- NonRecBind (
- foldr AndMonoBinds
- (foldr AndMonoBinds EmptyMonoBinds op_sel_binds)
- sc_sel_binds
- )))
-\end{code}
-
-%************************************************************************
-%* *
-\subsection[ClassDcl-misc]{Miscellaneous}
-%* *
-%************************************************************************
-
-Make a selector expression for @sel_id@ from a dictionary @clas_dict@
-consisting of @dicts@ and @methods@.
-
-====================== OLD ============================
-We have to do a bit of jiggery pokery to get the type variables right.
-Suppose we have the class decl:
-\begin{verbatim}
- class Foo a where
- op1 :: Ord b => a -> b -> a
- op2 :: ...
-\end{verbatim}
-Then the method selector for \tr{op1} is like this:
-\begin{verbatim}
- op1_sel = /\a b -> \dFoo dOrd -> case dFoo of
- (op1_method,op2_method) -> op1_method b dOrd
-\end{verbatim}
-Note that the type variable for \tr{b} and the (Ord b) dictionary
-are lifted to the top lambda, and
-\tr{op1_method} is applied to them. This is preferable to the alternative:
-\begin{verbatim}
- op1_sel' = /\a -> \dFoo -> case dFoo of
- (op1_method,op2_method) -> op1_method
-\end{verbatim}
-because \tr{op1_sel'} then has the rather strange type
-\begin{verbatim}
- op1_sel' :: forall a. Foo a -> forall b. Ord b -> a -> b -> a
-\end{verbatim}
-whereas \tr{op1_sel} (the one we use) has the decent type
-\begin{verbatim}
- op1_sel :: forall a b. Foo a -> Ord b -> a -> b -> a
-\end{verbatim}
-========================= END OF OLD ===========================
-
-NEW COMMENT: instead we now go for op1_sel' above. Seems tidier and
-the rest of the compiler darn well ought to cope.
-
-
-
-NOTE that we return a TcMonoBinds (which is later zonked) even though
-there's no real back-substitution to do. It's just simpler this way!
-
-NOTE ALSO that the selector has no free type variables, so we
-don't bother to instantiate the class-op's local type; instead
-we just use the variables inside it.
+ -- Generate bindings for the default methods
+ tcInstSigTyVars [tyvar] `thenNF_Tc` \ ([clas_tyvar], _, _) ->
+ mapAndUnzipTc (buildDefaultMethodBind clas clas_tyvar default_binds)
+ (op_sel_ids `zip` [0..])
+ `thenTc` \ (const_insts_s, meth_binds) ->
-\begin{code}
-mkSelBind :: Id -- the selector id
- -> TcTyVar s -> TcIdOcc s -- class tyvar and dict
- -> [TcIdOcc s] -> [TcIdOcc s] -- superclasses and methods in class dict
- -> TcIdOcc s -- the superclass/method being slected
- -> NF_TcM s (TcMonoBinds s)
-
-mkSelBind sel_id clas_tyvar clas_dict dicts methods method_or_dict@(TcId op)
- =
- -- sel_id = /\ clas_tyvar -> \ clas_dict ->
- -- case clas_dict of
- -- <dicts..methods> -> method_or_dict
-
- returnNF_Tc (VarMonoBind (RealId sel_id) (
- TyLam [clas_tyvar] (
- DictLam [clas_dict] (
- HsCase
- (HsVar clas_dict)
- ([PatMatch (DictPat dicts methods) (
- GRHSMatch (GRHSsAndBindsOut
- [OtherwiseGRHS
- (HsVar method_or_dict)
- mkGeneratedSrcLoc]
- EmptyBinds
- (idType op)))])
- mkGeneratedSrcLoc
- ))))
+ returnTc (unionManyBags const_insts_s,
+ final_sel_binds `ThenBinds`
+ MonoBind (andMonoBinds meth_binds) [] nonRecursive)
\end{code}
-
%************************************************************************
%* *
\subsection[Default methods]{Default methods}
\end{verbatim}
\begin{code}
-buildDefaultMethodBinds
+buildDefaultMethodBind
:: Class
-> TcTyVar s
- -> [Id]
-> RenamedMonoBinds
- -> TcM s (LIE s, TcHsBinds s)
+ -> (Id, Int)
+ -> TcM s (LIE s, TcMonoBinds s)
-buildDefaultMethodBinds clas clas_tyvar
- default_method_ids default_binds
+buildDefaultMethodBind clas clas_tyvar default_binds (sel_id, idx)
= newDicts origin [(clas,inst_ty)] `thenNF_Tc` \ (this_dict, [this_dict_id]) ->
- mapAndUnzipNF_Tc mk_method default_method_ids `thenNF_Tc` \ (insts_s, local_defm_ids) ->
let
- avail_insts = this_dict `plusLIE` unionManyBags insts_s -- Insts available
+ avail_insts = this_dict
+ defm_id = classDefaultMethodId clas idx
in
- processInstBinds
- clas
- (makeClassDeclDefaultMethodRhs clas local_defm_ids)
- [clas_tyvar] -- Tyvars in scope
- avail_insts
- local_defm_ids
- default_binds `thenTc` \ (insts_needed, default_binds') ->
+ tcExtendGlobalTyVars clas_tyvar_set (
+ tcMethodBind noDefmExpr inst_ty default_binds (sel_id, idx)
+ ) `thenTc` \ (defm_bind, insts_needed, (_, local_defm_id)) ->
+ -- CHECK THE CONTEXT OF THE DEFAULT-METHOD BINDS
tcSimplifyAndCheck
- (mkTyVarSet [clas_tyvar])
+ clas_tyvar_set
avail_insts
- insts_needed `thenTc` \ (const_lie, dict_binds) ->
-
+ insts_needed `thenTc` \ (const_lie, dict_binds) ->
let
defm_binds = AbsBinds
[clas_tyvar]
[this_dict_id]
- (local_defm_ids `zip` map RealId default_method_ids)
- dict_binds
- (RecBind default_binds')
+ [([clas_tyvar], RealId defm_id, local_defm_id)]
+ (dict_binds `AndMonoBinds` defm_bind)
in
returnTc (const_lie, defm_binds)
- where
- inst_ty = mkTyVarTy clas_tyvar
- mk_method defm_id = newMethodId defm_id inst_ty origin
- origin = ClassDeclOrigin
-\end{code}
-
-@makeClassDeclDefaultMethodRhs@ builds the default method for a
-class declaration when no explicit default method is given.
-
-\begin{code}
-makeClassDeclDefaultMethodRhs
- :: Class
- -> [TcIdOcc s]
- -> Int
- -> NF_TcM s (TcExpr s)
-
-makeClassDeclDefaultMethodRhs clas method_ids tag
- = -- Return the expression
- -- error ty "No default method for ..."
- -- The interesting thing is that method_ty is a for-all type;
- -- this is fun, although unusual in a type application!
-
- returnNF_Tc (HsApp (mkHsTyApp (HsVar (RealId nO_DEFAULT_METHOD_ERROR_ID)) [tcIdType method_id])
- (HsLitOut (HsString (_PK_ error_msg)) stringTy))
-
-{- OLD AND COMPLICATED
- tcInstSigType () `thenNF_Tc` \ method_ty ->
- let
- (tyvars, theta, tau) = splitSigmaTy method_ty
- in
- newDicts ClassDeclOrigin theta `thenNF_Tc` \ (lie, dict_ids) ->
-
- returnNF_Tc (mkHsTyLam tyvars (
- mkHsDictLam dict_ids (
- HsApp (mkHsTyApp (HsVar (RealId nO_DEFAULT_METHOD_ERROR_ID)) [tau])
- (HsLitOut (HsString (_PK_ error_msg)) stringTy))))
--}
where
- (OrigName clas_mod clas_name) = origName "makeClassDeclDefaultMethodRhs" clas
-
- method_id = method_ids !! (tag-1)
- class_op = (classOps clas) !! (tag-1)
-
- error_msg = _UNPK_ clas_mod ++ "." ++ _UNPK_ clas_name ++ "."
- ++ (ppShow 80 (ppr PprForUser class_op))
- ++ "\""
+ clas_tyvar_set = unitTyVarSet clas_tyvar
+ inst_ty = mkTyVarTy clas_tyvar
+ origin = ClassDeclOrigin
+ noDefmExpr _ = HsApp (HsVar (getName nO_DEFAULT_METHOD_ERROR_ID))
+ (HsLit (HsString (_PK_ error_msg)))
+
+ error_msg = show (sep [text "Class", ppr PprForUser clas,
+ text "Method", ppr PprForUser sel_id])
\end{code}
+
Contexts
~~~~~~~~
\begin{code}
classDeclCtxt class_name sty
- = ppCat [ppStr "In the class declaration for", ppr sty class_name]
+ = hsep [ptext SLIT("In the class declaration for"), ppr sty class_name]
\end{code}
projects / ghc-hetmet.git / blobdiff