X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcInstDcls.lhs;h=fe7b1d8b24254915b5335c724569cf62a4f874e7;hp=2d5967622e4686d48ca9de8b859d89fd28ce3acd;hb=84923cc7de2a93c22a2f72daf9ac863959efae13;hpb=1a0edd6c064a24042fa20c7014d11716a2d90a60 diff --git a/compiler/typecheck/TcInstDcls.lhs b/compiler/typecheck/TcInstDcls.lhs index 2d59676..fe7b1d8 100644 --- a/compiler/typecheck/TcInstDcls.lhs +++ b/compiler/typecheck/TcInstDcls.lhs @@ -1,7 +1,9 @@ % +% (c) The University of Glasgow 2006 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % -\section[TcInstDecls]{Typechecking instance declarations} + +TcInstDecls: Typechecking instance declarations \begin{code} module TcInstDcls ( tcInstDecls1, tcInstDecls2 ) where @@ -9,56 +11,43 @@ module TcInstDcls ( tcInstDecls1, tcInstDecls2 ) where #include "HsVersions.h" import HsSyn -import TcBinds ( mkPragFun, tcPrags, badBootDeclErr ) -import TcTyClsDecls ( tcIdxTyInstDecl ) -import TcClassDcl ( tcMethodBind, mkMethodBind, badMethodErr, badATErr, - omittedATWarn, tcClassDecl2, getGenericInstances ) +import TcBinds +import TcTyClsDecls +import TcClassDcl import TcRnMonad -import TcMType ( tcSkolSigType, checkValidInstance, - checkValidInstHead ) -import TcType ( TcType, mkClassPred, tcSplitSigmaTy, - tcSplitDFunHead, SkolemInfo(InstSkol), - tcSplitTyConApp, - tcSplitDFunTy, mkFunTy ) -import Inst ( newDictBndr, newDictBndrs, instToId, showLIE, - getOverlapFlag, tcExtendLocalInstEnv ) -import InstEnv ( mkLocalInstance, instanceDFunId ) -import FamInst ( tcExtendLocalFamInstEnv ) -import FamInstEnv ( extractFamInsts ) -import TcDeriv ( tcDeriving ) -import TcEnv ( InstInfo(..), InstBindings(..), - newDFunName, tcExtendIdEnv, tcExtendGlobalEnv - ) -import TcHsType ( kcHsSigType, tcHsKindedType ) -import TcUnify ( checkSigTyVars ) -import TcSimplify ( tcSimplifySuperClasses ) -import Type ( zipOpenTvSubst, substTheta, mkTyConApp, mkTyVarTy, - TyThing(ATyCon), isTyVarTy, tcEqType, - substTys, emptyTvSubst, extendTvSubst ) -import Coercion ( mkSymCoercion ) -import TyCon ( TyCon, tyConName, newTyConCo_maybe, tyConTyVars, - isTyConAssoc, tyConFamInst_maybe, tyConDataCons, - assocTyConArgPoss_maybe ) -import DataCon ( classDataCon, dataConInstArgTys ) -import Class ( Class, classTyCon, classBigSig, classATs ) -import Var ( TyVar, Id, idName, idType, tyVarName ) -import MkId ( mkDictFunId ) -import Name ( Name, getSrcLoc, nameOccName ) -import NameSet ( addListToNameSet, emptyNameSet, minusNameSet, - nameSetToList ) -import Maybe ( fromJust, catMaybes ) -import Monad ( when ) -import List ( find ) -import DynFlags ( DynFlag(Opt_WarnMissingMethods) ) -import SrcLoc ( srcLocSpan, unLoc, noLoc, Located(..), srcSpanStart, - getLoc) -import ListSetOps ( minusList ) -import Util ( snocView, dropList ) +import TcMType +import TcType +import Inst +import InstEnv +import FamInst +import FamInstEnv +import TcDeriv +import TcEnv +import TcHsType +import TcUnify +import TcSimplify +import Type +import Coercion +import TyCon +import DataCon +import Class +import Var +import MkId +import Name +import NameSet +import DynFlags +import SrcLoc +import ListSetOps +import Util import Outputable import Bag -import BasicTypes ( Activation( AlwaysActive ), InlineSpec(..) ) -import HscTypes ( implicitTyThings ) +import BasicTypes +import HscTypes import FastString + +import Data.Maybe +import Control.Monad hiding (zipWithM_, mapAndUnzipM) +import Data.List \end{code} Typechecking instance declarations is done in two passes. The first @@ -146,12 +135,13 @@ Gather up the instance declarations from their various sources tcInstDecls1 -- Deal with both source-code and imported instance decls :: [LTyClDecl Name] -- For deriving stuff -> [LInstDecl Name] -- Source code instance decls + -> [LDerivDecl Name] -- Source code stand-alone deriving decls -> TcM (TcGblEnv, -- The full inst env [InstInfo], -- Source-code instance decls to process; -- contains all dfuns for this module HsValBinds Name) -- Supporting bindings for derived instances -tcInstDecls1 tycl_decls inst_decls +tcInstDecls1 tycl_decls inst_decls deriv_decls = checkNoErrs $ do { -- Stop if addInstInfos etc discovers any errors -- (they recover, so that we get more than one error each @@ -190,7 +180,7 @@ tcInstDecls1 tycl_decls inst_decls -- (4) Compute instances from "deriving" clauses; -- This stuff computes a context for the derived instance -- decl, so it needs to know about all the instances possible - ; (deriv_inst_info, deriv_binds) <- tcDeriving tycl_decls + ; (deriv_inst_info, deriv_binds) <- tcDeriving tycl_decls deriv_decls ; addInsts deriv_inst_info $ do { ; gbl_env <- getGblEnv @@ -226,8 +216,12 @@ addInsts infos thing_inside addFamInsts :: [TyThing] -> TcM a -> TcM a addFamInsts tycons thing_inside - = tcExtendLocalFamInstEnv (extractFamInsts tycons) thing_inside -\end{code} + = tcExtendLocalFamInstEnv (map mkLocalFamInstTyThing tycons) thing_inside + where + mkLocalFamInstTyThing (ATyCon tycon) = mkLocalFamInst tycon + mkLocalFamInstTyThing tything = pprPanic "TcInstDcls.addFamInsts" + (ppr tything) +\end{code} \begin{code} tcLocalInstDecl1 :: LInstDecl Name @@ -246,11 +240,7 @@ tcLocalInstDecl1 decl@(L loc (InstDecl poly_ty binds uprags ats)) ; checkTc (not is_boot || (isEmptyLHsBinds binds && null uprags)) badBootDeclErr - -- Typecheck the instance type itself. We can't use - -- tcHsSigType, because it's not a valid user type. - ; kinded_ty <- kcHsSigType poly_ty - ; poly_ty' <- tcHsKindedType kinded_ty - ; let (tyvars, theta, tau) = tcSplitSigmaTy poly_ty' + ; (tyvars, theta, tau) <- tcHsInstHead poly_ty -- Next, process any associated types. ; idx_tycons <- mappM tcIdxTyInstDecl ats @@ -489,7 +479,7 @@ tcInstDecl2 :: InstInfo -> TcM (LHsBinds Id) tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = NewTypeDerived mb_preds }) = do { let dfun_id = instanceDFunId ispec - rigid_info = InstSkol dfun_id + rigid_info = InstSkol origin = SigOrigin rigid_info inst_ty = idType dfun_id ; (tvs, theta, inst_head_ty) <- tcSkolSigType rigid_info inst_ty @@ -505,11 +495,11 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = NewTypeDerived mb_preds }) ; let (cls, cls_inst_tys) = tcSplitDFunHead inst_head_ty cls_tycon = classTyCon cls the_coercion = make_coercion cls_tycon cls_inst_tys - coerced_rep_dict = mkHsCoerce the_coercion (HsVar rep_dict_id) + coerced_rep_dict = mkHsWrap the_coercion (HsVar rep_dict_id) ; body <- make_body cls_tycon cls_inst_tys sc_dict_ids coerced_rep_dict - ; return (sc_binds `snocBag` (noLoc $ VarBind dfun_id $ noLoc $ mkHsCoerce wrap_fn body)) } + ; return (sc_binds `snocBag` (noLoc $ VarBind dfun_id $ noLoc $ mkHsWrap wrap_fn body)) } where ----------------------- @@ -524,15 +514,16 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = NewTypeDerived mb_preds }) make_wrapper inst_loc tvs theta (Just preds) -- Case (a) = ASSERT( null tvs && null theta ) do { dicts <- newDictBndrs inst_loc preds - ; sc_binds <- addErrCtxt superClassCtxt (tcSimplifySuperClasses [] [] dicts) + ; sc_binds <- addErrCtxt superClassCtxt $ + tcSimplifySuperClasses inst_loc [] dicts -- Use tcSimplifySuperClasses to avoid creating loops, for the -- same reason as Note [SUPERCLASS-LOOP 1] in TcSimplify - ; return (map instToId dicts, idCoercion, sc_binds) } + ; return (map instToId dicts, idHsWrapper, sc_binds) } make_wrapper inst_loc tvs theta Nothing -- Case (b) = do { dicts <- newDictBndrs inst_loc theta ; let dict_ids = map instToId dicts - ; return (dict_ids, mkCoTyLams tvs <.> mkCoLams dict_ids, emptyBag) } + ; return (dict_ids, mkWpTyLams tvs <.> mkWpLams dict_ids, emptyBag) } ----------------------- -- make_coercion @@ -548,9 +539,9 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = NewTypeDerived mb_preds }) , (tycon, tc_args) <- tcSplitTyConApp last_ty -- Should not fail , Just co_con <- newTyConCo_maybe tycon , let co = mkSymCoercion (mkTyConApp co_con tc_args) - = ExprCoFn (mkTyConApp cls_tycon (all_tys_but_last ++ [co])) + = WpCo (mkTyConApp cls_tycon (all_tys_but_last ++ [co])) | otherwise -- The newtype is transparent; no need for a cast - = idCoercion + = idHsWrapper ----------------------- -- make_body @@ -590,7 +581,7 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = NewTypeDerived mb_preds }) tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = VanillaInst monobinds uprags }) = let dfun_id = instanceDFunId ispec - rigid_info = InstSkol dfun_id + rigid_info = InstSkol inst_ty = idType dfun_id in -- Prime error recovery @@ -616,7 +607,7 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = VanillaInst monobinds uprags }) newDictBndrs sc_loc sc_theta' `thenM` \ sc_dicts -> getInstLoc origin `thenM` \ inst_loc -> newDictBndrs inst_loc dfun_theta' `thenM` \ dfun_arg_dicts -> - newDictBndr inst_loc (mkClassPred clas inst_tys') `thenM` \ this_dict -> + newDictBndr inst_loc (mkClassPred clas inst_tys') `thenM` \ this_dict -> -- Default-method Ids may be mentioned in synthesised RHSs, -- but they'll already be in the environment. @@ -632,9 +623,8 @@ tcInstDecl2 (InstInfo { iSpec = ispec, iBinds = VanillaInst monobinds uprags }) -- Don't include this_dict in the 'givens', else -- sc_dicts get bound by just selecting from this_dict!! addErrCtxt superClassCtxt - (tcSimplifySuperClasses inst_tyvars' - dfun_arg_dicts - sc_dicts) `thenM` \ sc_binds -> + (tcSimplifySuperClasses inst_loc + dfun_arg_dicts sc_dicts) `thenM` \ sc_binds -> -- It's possible that the superclass stuff might unified one -- of the inst_tyavars' with something in the envt