import TcHsSyn ( TcExpr, TcRecordBinds, simpleHsLitTy )
import TcMonad
-import TcUnify ( tcSub, tcGen, (<$>),
+import TcUnify ( tcSubExp, tcGen, (<$>),
unifyTauTy, unifyFunTy, unifyListTy, unifyPArrTy,
unifyTupleTy )
import BasicTypes ( RecFlag(..), isMarkedStrict )
import TcMonoType ( tcHsSigType, UserTypeCtxt(..) )
import TcPat ( badFieldCon )
import TcSimplify ( tcSimplifyIPs )
-import TcMType ( tcInstTyVars, tcInstType, newHoleTyVarTy,
- newTyVarTy, newTyVarTys, zonkTcType )
-import TcType ( TcType, TcSigmaType, TcPhiType,
+import TcMType ( tcInstTyVars, tcInstType, newHoleTyVarTy, zapToType,
+ newTyVarTy, newTyVarTys, zonkTcType, readHoleResult )
+import TcType ( TcType, TcSigmaType, TcRhoType, TyVarDetails(VanillaTv),
tcSplitFunTys, tcSplitTyConApp, mkTyVarTys,
isSigmaTy, mkFunTy, mkAppTy, mkTyConTy,
mkTyConApp, mkClassPred, tcFunArgTy,
import Name ( Name )
import TyCon ( TyCon, tyConTyVars, isAlgTyCon, tyConDataCons )
import Subst ( mkTopTyVarSubst, substTheta, substTy )
-import VarSet ( elemVarSet )
+import VarSet ( emptyVarSet, elemVarSet )
import TysWiredIn ( boolTy, mkListTy, mkPArrTy, listTyCon, parrTyCon )
import PrelNames ( cCallableClassName,
cReturnableClassName,
= tcMonoExpr expr expected_ty
| otherwise
- = tcGen expected_ty (tcMonoExpr expr) `thenTc` \ (gen_fn, expr', lie) ->
+ = tcGen expected_ty emptyVarSet (
+ tcMonoExpr expr
+ ) `thenTc` \ (gen_fn, expr', lie) ->
returnTc (gen_fn <$> expr', lie)
\end{code}
\begin{code}
tcMonoExpr :: RenamedHsExpr -- Expession to type check
- -> TcPhiType -- Expected type (could be a type variable)
+ -> TcRhoType -- Expected type (could be a type variable)
-- Definitely no foralls at the top
-- Can be a 'hole'.
-> TcM (TcExpr, LIE)
tcMonoExpr (HsVar name) res_ty
= tcId name `thenNF_Tc` \ (expr', lie1, id_ty) ->
- tcSub res_ty id_ty `thenTc` \ (co_fn, lie2) ->
+ tcSubExp res_ty id_ty `thenTc` \ (co_fn, lie2) ->
returnTc (co_fn <$> expr', lie1 `plusLIE` lie2)
tcMonoExpr (HsIPVar ip) res_ty
-- be a tau-type.)
newTyVarTy openTypeKind `thenNF_Tc` \ ip_ty ->
newIPDict (IPOcc ip) ip ip_ty `thenNF_Tc` \ (ip', inst) ->
- tcSub res_ty ip_ty `thenTc` \ (co_fn, lie) ->
+ tcSubExp res_ty ip_ty `thenTc` \ (co_fn, lie) ->
returnNF_Tc (co_fn <$> HsIPVar ip', lie `plusLIE` unitLIE inst)
\end{code}
\begin{code}
tcMonoExpr in_expr@(ExprWithTySig expr poly_ty) res_ty
= tcHsSigType ExprSigCtxt poly_ty `thenTc` \ sig_tc_ty ->
- tcAddErrCtxt (exprSigCtxt in_expr) $
tcExpr expr sig_tc_ty `thenTc` \ (expr', lie1) ->
-- Must instantiate the outer for-alls of sig_tc_ty
-- else we risk instantiating a ? res_ty to a forall-type
-- which breaks the invariant that tcMonoExpr only returns phi-types
+ tcAddErrCtxt (exprSigCtxt in_expr) $
tcInstCall SignatureOrigin sig_tc_ty `thenNF_Tc` \ (inst_fn, lie2, inst_sig_ty) ->
- tcSub res_ty inst_sig_ty `thenTc` \ (co_fn, lie3) ->
+ tcSubExp res_ty inst_sig_ty `thenTc` \ (co_fn, lie3) ->
returnTc (co_fn <$> inst_fn expr', lie1 `plusLIE` lie2 `plusLIE` lie3)
\end{code}
split_fun_ty op_ty 2 {- two args -} `thenTc` \ ([arg1_ty, arg2_ty], op_res_ty) ->
tcArg op (arg1, arg1_ty, 1) `thenTc` \ (arg1',lie2) ->
tcAddErrCtxt (exprCtxt in_expr) $
- tcSub res_ty (mkFunTy arg2_ty op_res_ty) `thenTc` \ (co_fn, lie3) ->
+ tcSubExp res_ty (mkFunTy arg2_ty op_res_ty) `thenTc` \ (co_fn, lie3) ->
returnTc (co_fn <$> SectionL arg1' op', lie1 `plusLIE` lie2 `plusLIE` lie3)
-- Right sections, equivalent to \ x -> x op expr, or
split_fun_ty op_ty 2 {- two args -} `thenTc` \ ([arg1_ty, arg2_ty], op_res_ty) ->
tcArg op (arg2, arg2_ty, 2) `thenTc` \ (arg2',lie2) ->
tcAddErrCtxt (exprCtxt in_expr) $
- tcSub res_ty (mkFunTy arg1_ty op_res_ty) `thenTc` \ (co_fn, lie3) ->
+ tcSubExp res_ty (mkFunTy arg1_ty op_res_ty) `thenTc` \ (co_fn, lie3) ->
returnTc (co_fn <$> SectionR op' arg2', lie1 `plusLIE` lie2 `plusLIE` lie3)
-- equivalent to (op e1) e2:
tcArg op (arg1, arg1_ty, 1) `thenTc` \ (arg1',lie2a) ->
tcArg op (arg2, arg2_ty, 2) `thenTc` \ (arg2',lie2b) ->
tcAddErrCtxt (exprCtxt in_expr) $
- tcSub res_ty op_res_ty `thenTc` \ (co_fn, lie3) ->
+ tcSubExp res_ty op_res_ty `thenTc` \ (co_fn, lie3) ->
returnTc (OpApp arg1' op' fix arg2',
lie1 `plusLIE` lie2a `plusLIE` lie2b `plusLIE` lie3)
\end{code}
tcAddErrCtxt (predCtxt pred) (
tcMonoExpr pred boolTy ) `thenTc` \ (pred',lie1) ->
- tcMonoExpr b1 res_ty `thenTc` \ (b1',lie2) ->
- tcMonoExpr b2 res_ty `thenTc` \ (b2',lie3) ->
+ zapToType res_ty `thenTc` \ res_ty' ->
+ -- C.f. the call to zapToType in TcMatches.tcMatches
+
+ tcMonoExpr b1 res_ty' `thenTc` \ (b1',lie2) ->
+ tcMonoExpr b2 res_ty' `thenTc` \ (b2',lie3) ->
returnTc (HsIf pred' b1' b2' src_loc, plusLIE lie1 (plusLIE lie2 lie3))
\end{code}
data_cons = tyConDataCons tycon
(con_tyvars, _, _, _, _, _) = dataConSig (head data_cons)
in
- tcInstTyVars con_tyvars `thenNF_Tc` \ (_, result_inst_tys, _) ->
+ tcInstTyVars VanillaTv con_tyvars `thenNF_Tc` \ (_, result_inst_tys, _) ->
-- STEP 2
-- Check that at least one constructor has all the named fields
mk_inst_ty (tyvar, result_inst_ty)
| tyvar `elemVarSet` common_tyvars = returnNF_Tc result_inst_ty -- Same as result type
- | otherwise = newTyVarTy liftedTypeKind -- Fresh type
+ | otherwise = newTyVarTy liftedTypeKind -- Fresh type
in
mapNF_Tc mk_inst_ty (zip con_tyvars result_inst_tys) `thenNF_Tc` \ inst_tys ->
tcExpr_id fun `thenTc` \ (fun', lie_fun, fun_ty) ->
tcAddErrCtxt (wrongArgsCtxt "too many" fun args) (
+ traceTc (text "tcApp" <+> (ppr fun $$ ppr fun_ty)) `thenNF_Tc_`
split_fun_ty fun_ty (length args)
) `thenTc` \ (expected_arg_tys, actual_result_ty) ->
-- (One can think of cases when the opposite order would give
-- a better error message.)
tcAddErrCtxtM (checkArgsCtxt fun args res_ty actual_result_ty)
- (tcSub res_ty actual_result_ty) `thenTc` \ (co_fn, lie_res) ->
+ (tcSubExp res_ty actual_result_ty) `thenTc` \ (co_fn, lie_res) ->
returnTc (co_fn <$> foldl HsApp fun' args',
lie_res `plusLIE` lie_fun `plusLIE` plusLIEs lie_args_s)
where
loop orig (HsVar fun_id) lie fun_ty
| want_method_inst fun_ty
- = tcInstType fun_ty `thenNF_Tc` \ (tyvars, theta, tau) ->
+ = tcInstType VanillaTv fun_ty `thenNF_Tc` \ (tyvars, theta, tau) ->
newMethodWithGivenTy orig fun_id
(mkTyVarTys tyvars) theta tau `thenNF_Tc` \ meth ->
loop orig (HsVar (instToId meth))
tcExpr_id (HsVar name) = tcId name
tcExpr_id expr = newHoleTyVarTy `thenNF_Tc` \ id_ty ->
tcMonoExpr expr id_ty `thenTc` \ (expr', lie_id) ->
- returnTc (expr', lie_id, id_ty)
+ readHoleResult id_ty `thenTc` \ id_ty' ->
+ returnTc (expr', lie_id, id_ty')
\end{code}
= hang (ptext SLIT("In the scrutinee of a case expression:")) 4 (ppr expr)
exprSigCtxt expr
- = hang (ptext SLIT("In an expression with a type signature:"))
+ = hang (ptext SLIT("When checking the type signature of the expression:"))
4 (ppr expr)
listCtxt expr
projects / ghc-hetmet.git / blobdiff