#include "HsVersions.h"
import HsSyn ( HsExpr(..), HsLit(..), ArithSeqInfo(..),
- MonoBinds(..), StmtCtxt(..),
- mkMonoBind, nullMonoBinds
+ HsMatchContext(..), HsDoContext(..), mkMonoBind
)
import RnHsSyn ( RenamedHsExpr, RenamedRecordBinds )
-import TcHsSyn ( TcExpr, TcRecordBinds, mkHsTyApp, mkHsLet )
+import TcHsSyn ( TcExpr, TcRecordBinds, mkHsLet )
import TcMonad
import BasicTypes ( RecFlag(..) )
import Inst ( InstOrigin(..),
- LIE, emptyLIE, unitLIE, plusLIE, plusLIEs,
+ LIE, mkLIE, emptyLIE, unitLIE, plusLIE, plusLIEs,
newOverloadedLit, newMethod, newIPDict,
- instOverloadedFun, newDicts, newClassDicts,
- getIPsOfLIE, instToId, ipToId
+ newDicts,
+ instToId, tcInstId
)
import TcBinds ( tcBindsAndThen )
-import TcEnv ( TcTyThing(..), tcInstId,
- tcLookupClass, tcLookupGlobalId, tcLookupGlobal_maybe,
- tcLookupTyCon, tcLookupDataCon, tcLookup,
- tcExtendGlobalTyVars
+import TcEnv ( tcLookupClass, tcLookupGlobalId, tcLookupGlobal_maybe,
+ tcLookupTyCon, tcLookupDataCon, tcLookupId,
+ tcExtendGlobalTyVars, tcLookupSyntaxName
)
import TcMatches ( tcMatchesCase, tcMatchLambda, tcStmts )
import TcMonoType ( tcHsSigType, checkSigTyVars, sigCtxt )
import TcPat ( badFieldCon, simpleHsLitTy )
-import TcSimplify ( tcSimplifyAndCheck, partitionPredsOfLIE )
-import TcImprove ( tcImprove )
-import TcType ( TcType, TcTauType,
- tcInstTyVars,
- tcInstTcType, tcSplitRhoTy,
- newTyVarTy, newTyVarTys, zonkTcType )
-
-import FieldLabel ( fieldLabelName, fieldLabelType, fieldLabelTyCon )
-import Id ( idType, recordSelectorFieldLabel, isRecordSelector, mkVanillaId )
-import DataCon ( dataConFieldLabels, dataConSig,
- dataConStrictMarks, StrictnessMark(..)
+import TcSimplify ( tcSimplifyCheck, tcSimplifyIPs )
+import TcMType ( tcInstTyVars, tcInstType,
+ newTyVarTy, newTyVarTys, zonkTcType,
+ unifyTauTy, unifyFunTy, unifyListTy, unifyTupleTy
)
-import Name ( Name, getName )
-import Type ( mkFunTy, mkAppTy, mkTyVarTys, ipName_maybe,
- splitFunTy_maybe, splitFunTys,
- mkTyConApp, splitSigmaTy,
- splitRhoTy,
+import TcType ( tcSplitFunTys, tcSplitTyConApp,
+ isQualifiedTy,
+ mkFunTy, mkAppTy, mkTyConTy,
+ mkTyConApp, mkClassPred, tcFunArgTy,
isTauTy, tyVarsOfType, tyVarsOfTypes,
- isSigmaTy, splitAlgTyConApp, splitAlgTyConApp_maybe,
- boxedTypeKind, openTypeKind, mkArrowKind,
+ liftedTypeKind, openTypeKind, mkArrowKind,
+ tcSplitSigmaTy, tcTyConAppTyCon,
tidyOpenType
)
-import TyCon ( TyCon, tyConTyVars )
-import Subst ( mkTopTyVarSubst, substClasses, substTy )
-import VarSet ( elemVarSet, mkVarSet )
-import TysWiredIn ( boolTy )
-import TcUnify ( unifyTauTy, unifyFunTy, unifyListTy, unifyTupleTy )
+import FieldLabel ( FieldLabel, fieldLabelName, fieldLabelType, fieldLabelTyCon )
+import Id ( idType, recordSelectorFieldLabel, isRecordSelector )
+import DataCon ( dataConFieldLabels, dataConSig,
+ dataConStrictMarks
+ )
+import Demand ( isMarkedStrict )
+import Name ( Name )
+import TyCon ( TyCon, tyConTyVars, isAlgTyCon, tyConDataCons )
+import Subst ( mkTopTyVarSubst, substTheta, substTy )
+import VarSet ( elemVarSet )
+import TysWiredIn ( boolTy, mkListTy, listTyCon )
import PrelNames ( cCallableClassName,
cReturnableClassName,
- enumFromName, enumFromThenName,
+ enumFromName, enumFromThenName, negateName,
enumFromToName, enumFromThenToName,
thenMName, failMName, returnMName, ioTyConName
)
import Outputable
-import Maybes ( maybeToBool, mapMaybe )
import ListSetOps ( minusList )
import Util
import CmdLineOpts
-> TcType -- Expected type (could be a polytpye)
-> TcM (TcExpr, LIE)
-tcExpr expr ty | isSigmaTy ty = -- Polymorphic case
- tcPolyExpr expr ty `thenTc` \ (expr', lie, _, _, _) ->
- returnTc (expr', lie)
+tcExpr expr ty | isQualifiedTy ty = -- Polymorphic case
+ tcPolyExpr expr ty `thenTc` \ (expr', lie, _, _, _) ->
+ returnTc (expr', lie)
- | otherwise = -- Monomorphic case
- tcMonoExpr expr ty
+ | otherwise = -- Monomorphic case
+ tcMonoExpr expr ty
\end{code}
-- To ensure that the forall'd type variables don't get unified with each
-- other or any other types, we make fresh copy of the alleged type
- tcInstTcType expected_arg_ty `thenNF_Tc` \ (sig_tyvars, sig_rho) ->
+ tcInstType expected_arg_ty `thenNF_Tc` \ (sig_tyvars, sig_theta, sig_tau) ->
let
- (sig_theta, sig_tau) = splitRhoTy sig_rho
- free_tyvars = tyVarsOfType expected_arg_ty
+ free_tvs = tyVarsOfType expected_arg_ty
in
-- Type-check the arg and unify with expected type
tcMonoExpr arg sig_tau `thenTc` \ (arg', lie_arg) ->
-- Conclusion: include the free vars of the expected arg type in the
-- list of "free vars" for the signature check.
- tcExtendGlobalTyVars free_tyvars $
+ tcExtendGlobalTyVars free_tvs $
tcAddErrCtxtM (sigCtxt sig_msg sig_tyvars sig_theta sig_tau) $
- checkSigTyVars sig_tyvars free_tyvars `thenTc` \ zonked_sig_tyvars ->
-
- newDicts SignatureOrigin sig_theta `thenNF_Tc` \ (sig_dicts, dict_ids) ->
- tcImprove (sig_dicts `plusLIE` lie_arg) `thenTc_`
- -- ToDo: better origin
- tcSimplifyAndCheck
+ newDicts SignatureOrigin sig_theta `thenNF_Tc` \ sig_dicts ->
+ tcSimplifyCheck
(text "the type signature of an expression")
- (mkVarSet zonked_sig_tyvars)
+ sig_tyvars
sig_dicts lie_arg `thenTc` \ (free_insts, inst_binds) ->
+ checkSigTyVars sig_tyvars free_tvs `thenTc` \ zonked_sig_tyvars ->
+
let
-- This HsLet binds any Insts which came out of the simplification.
-- It's a bit out of place here, but using AbsBind involves inventing
-- a couple of new names which seems worse.
generalised_arg = TyLam zonked_sig_tyvars $
- DictLam dict_ids $
+ DictLam (map instToId sig_dicts) $
mkHsLet inst_binds $
arg'
in
\begin{code}
tcMonoExpr (HsIPVar name) res_ty
- -- ZZ What's the `id' used for here...
- = let id = mkVanillaId name res_ty in
- tcGetInstLoc (OccurrenceOf id) `thenNF_Tc` \ loc ->
- newIPDict name res_ty loc `thenNF_Tc` \ ip ->
+ = newIPDict (IPOcc name) name res_ty `thenNF_Tc` \ ip ->
returnNF_Tc (HsIPVar (instToId ip), unitLIE ip)
\end{code}
tcMonoExpr (HsOverLit lit) res_ty = newOverloadedLit (LiteralOrigin lit) lit res_ty
tcMonoExpr (HsPar expr) res_ty = tcMonoExpr expr res_ty
-tcMonoExpr (NegApp expr neg) res_ty
- = tcMonoExpr (HsApp (HsVar neg) expr) res_ty
+tcMonoExpr (NegApp expr) res_ty
+ = tcLookupSyntaxName negateName `thenNF_Tc` \ neg ->
+ tcMonoExpr (HsApp (HsVar neg) expr) res_ty
tcMonoExpr (HsLam match) res_ty
= tcMatchLambda match res_ty `thenTc` \ (match',lie) ->
tcLookupTyCon ioTyConName `thenNF_Tc` \ ioTyCon ->
let
new_arg_dict (arg, arg_ty)
- = newClassDicts (CCallOrigin (_UNPK_ lbl) (Just arg))
- [(cCallableClass, [arg_ty])] `thenNF_Tc` \ (arg_dicts, _) ->
+ = newDicts (CCallOrigin (_UNPK_ lbl) (Just arg))
+ [mkClassPred cCallableClass [arg_ty]] `thenNF_Tc` \ arg_dicts ->
returnNF_Tc arg_dicts -- Actually a singleton bag
result_origin = CCallOrigin (_UNPK_ lbl) Nothing {- Not an arg -}
newTyVarTys (length tv_idxs) openTypeKind `thenNF_Tc` \ arg_tys ->
tcMonoExprs args arg_tys `thenTc` \ (args', args_lie) ->
- -- The argument types can be unboxed or boxed; the result
- -- type must, however, be boxed since it's an argument to the IO
+ -- The argument types can be unlifted or lifted; the result
+ -- type must, however, be lifted since it's an argument to the IO
-- type constructor.
- newTyVarTy boxedTypeKind `thenNF_Tc` \ result_ty ->
+ newTyVarTy liftedTypeKind `thenNF_Tc` \ result_ty ->
let
io_result_ty = mkTyConApp ioTyCon [result_ty]
in
-- Construct the extra insts, which encode the
-- constraints on the argument and result types.
mapNF_Tc new_arg_dict (zipEqual "tcMonoExpr:CCall" args arg_tys) `thenNF_Tc` \ ccarg_dicts_s ->
- newClassDicts result_origin [(cReturnableClass, [result_ty])] `thenNF_Tc` \ (ccres_dict, _) ->
+ newDicts result_origin [mkClassPred cReturnableClass [result_ty]] `thenNF_Tc` \ ccres_dict ->
returnTc (HsCCall lbl args' may_gc is_asm io_result_ty,
- foldr plusLIE ccres_dict ccarg_dicts_s `plusLIE` args_lie)
+ mkLIE (ccres_dict ++ concat ccarg_dicts_s) `plusLIE` args_lie)
\end{code}
\begin{code}
= tcAddErrCtxt (recordConCtxt expr) $
tcId con_name `thenNF_Tc` \ (con_expr, con_lie, con_tau) ->
let
- (_, record_ty) = splitFunTys con_tau
- (tycon, ty_args, _) = splitAlgTyConApp record_ty
+ (_, record_ty) = tcSplitFunTys con_tau
+ (tycon, ty_args) = tcSplitTyConApp record_ty
in
- ASSERT( maybeToBool (splitAlgTyConApp_maybe record_ty ) )
+ ASSERT( isAlgTyCon tycon )
unifyTauTy res_ty record_ty `thenTc_`
-- Check that the record bindings match the constructor
tcRecordBinds tycon ty_args rbinds `thenTc` \ (rbinds', rbinds_lie) ->
let
- missing_s_fields = missingStrictFields rbinds data_con
+ (missing_s_fields, missing_fields) = missingFields rbinds data_con
in
checkTcM (null missing_s_fields)
(mapNF_Tc (addErrTc . missingStrictFieldCon con_name) missing_s_fields `thenNF_Tc_`
returnNF_Tc ()) `thenNF_Tc_`
- let
- missing_fields = missingFields rbinds data_con
- in
doptsTc Opt_WarnMissingFields `thenNF_Tc` \ warn ->
checkTcM (not (warn && not (null missing_fields)))
(mapNF_Tc ((warnTc True) . missingFieldCon con_name) missing_fields `thenNF_Tc_`
-- STEP 1
-- Figure out the tycon and data cons from the first field name
let
- (Just (AnId sel_id) : _) = maybe_sel_ids
- (_, _, tau) = splitSigmaTy (idType sel_id) -- Selectors can be overloaded
+ -- It's OK to use the non-tc splitters here (for a selector)
+ (Just (AnId sel_id) : _) = maybe_sel_ids
+ (_, _, tau) = tcSplitSigmaTy (idType sel_id) -- Selectors can be overloaded
-- when the data type has a context
- Just (data_ty, _) = splitFunTy_maybe tau -- Must succeed since sel_id is a selector
- (tycon, _, data_cons) = splitAlgTyConApp data_ty
+ data_ty = tcFunArgTy tau -- Must succeed since sel_id is a selector
+ tycon = tcTyConAppTyCon data_ty
+ data_cons = tyConDataCons tycon
(con_tyvars, _, _, _, _, _) = dataConSig (head data_cons)
in
tcInstTyVars con_tyvars `thenNF_Tc` \ (_, result_inst_tys, _) ->
mk_inst_ty (tyvar, result_inst_ty)
| tyvar `elemVarSet` common_tyvars = returnNF_Tc result_inst_ty -- Same as result type
- | otherwise = newTyVarTy boxedTypeKind -- Fresh type
+ | otherwise = newTyVarTy liftedTypeKind -- Fresh type
in
mapNF_Tc mk_inst_ty (zip con_tyvars result_inst_tys) `thenNF_Tc` \ inst_tys ->
let
(tyvars, theta, _, _, _, _) = dataConSig (head data_cons)
inst_env = mkTopTyVarSubst tyvars result_inst_tys
- theta' = substClasses inst_env theta
+ theta' = substTheta inst_env theta
in
- newClassDicts RecordUpdOrigin theta' `thenNF_Tc` \ (con_lie, dicts) ->
+ newDicts RecordUpdOrigin theta' `thenNF_Tc` \ dicts ->
-- Phew!
- returnTc (RecordUpdOut record_expr' result_record_ty dicts rbinds',
- con_lie `plusLIE` record_lie `plusLIE` rbinds_lie)
+ returnTc (RecordUpdOut record_expr' result_record_ty (map instToId dicts) rbinds',
+ mkLIE dicts `plusLIE` record_lie `plusLIE` rbinds_lie)
tcMonoExpr (ArithSeqIn seq@(From expr)) res_ty
= unifyListTy res_ty `thenTc` \ elt_ty ->
tcLookupGlobalId enumFromName `thenNF_Tc` \ sel_id ->
newMethod (ArithSeqOrigin seq)
- sel_id [elt_ty] `thenNF_Tc` \ (lie2, enum_from_id) ->
+ sel_id [elt_ty] `thenNF_Tc` \ enum_from ->
- returnTc (ArithSeqOut (HsVar enum_from_id) (From expr'),
- lie1 `plusLIE` lie2)
+ returnTc (ArithSeqOut (HsVar (instToId enum_from)) (From expr'),
+ lie1 `plusLIE` unitLIE enum_from)
tcMonoExpr in_expr@(ArithSeqIn seq@(FromThen expr1 expr2)) res_ty
= tcAddErrCtxt (arithSeqCtxt in_expr) $
tcMonoExpr expr1 elt_ty `thenTc` \ (expr1',lie1) ->
tcMonoExpr expr2 elt_ty `thenTc` \ (expr2',lie2) ->
tcLookupGlobalId enumFromThenName `thenNF_Tc` \ sel_id ->
- newMethod (ArithSeqOrigin seq) sel_id [elt_ty] `thenNF_Tc` \ (lie3, enum_from_then_id) ->
+ newMethod (ArithSeqOrigin seq) sel_id [elt_ty] `thenNF_Tc` \ enum_from_then ->
- returnTc (ArithSeqOut (HsVar enum_from_then_id)
- (FromThen expr1' expr2'),
- lie1 `plusLIE` lie2 `plusLIE` lie3)
+ returnTc (ArithSeqOut (HsVar (instToId enum_from_then))
+ (FromThen expr1' expr2'),
+ lie1 `plusLIE` lie2 `plusLIE` unitLIE enum_from_then)
tcMonoExpr in_expr@(ArithSeqIn seq@(FromTo expr1 expr2)) res_ty
= tcAddErrCtxt (arithSeqCtxt in_expr) $
tcMonoExpr expr1 elt_ty `thenTc` \ (expr1',lie1) ->
tcMonoExpr expr2 elt_ty `thenTc` \ (expr2',lie2) ->
tcLookupGlobalId enumFromToName `thenNF_Tc` \ sel_id ->
- newMethod (ArithSeqOrigin seq) sel_id [elt_ty] `thenNF_Tc` \ (lie3, enum_from_to_id) ->
+ newMethod (ArithSeqOrigin seq) sel_id [elt_ty] `thenNF_Tc` \ enum_from_to ->
- returnTc (ArithSeqOut (HsVar enum_from_to_id)
+ returnTc (ArithSeqOut (HsVar (instToId enum_from_to))
(FromTo expr1' expr2'),
- lie1 `plusLIE` lie2 `plusLIE` lie3)
+ lie1 `plusLIE` lie2 `plusLIE` unitLIE enum_from_to)
tcMonoExpr in_expr@(ArithSeqIn seq@(FromThenTo expr1 expr2 expr3)) res_ty
= tcAddErrCtxt (arithSeqCtxt in_expr) $
tcMonoExpr expr2 elt_ty `thenTc` \ (expr2',lie2) ->
tcMonoExpr expr3 elt_ty `thenTc` \ (expr3',lie3) ->
tcLookupGlobalId enumFromThenToName `thenNF_Tc` \ sel_id ->
- newMethod (ArithSeqOrigin seq) sel_id [elt_ty] `thenNF_Tc` \ (lie4, eft_id) ->
+ newMethod (ArithSeqOrigin seq) sel_id [elt_ty] `thenNF_Tc` \ eft ->
- returnTc (ArithSeqOut (HsVar eft_id)
- (FromThenTo expr1' expr2' expr3'),
- lie1 `plusLIE` lie2 `plusLIE` lie3 `plusLIE` lie4)
+ returnTc (ArithSeqOut (HsVar (instToId eft))
+ (FromThenTo expr1' expr2' expr3'),
+ lie1 `plusLIE` lie2 `plusLIE` lie3 `plusLIE` unitLIE eft)
\end{code}
%************************************************************************
\begin{code}
tcMonoExpr in_expr@(ExprWithTySig expr poly_ty) res_ty
- = tcSetErrCtxt (exprSigCtxt in_expr) $
+ = tcAddErrCtxt (exprSigCtxt in_expr) $
tcHsSigType poly_ty `thenTc` \ sig_tc_ty ->
- if not (isSigmaTy sig_tc_ty) then
+ if not (isQualifiedTy sig_tc_ty) then
-- Easy case
unifyTauTy sig_tc_ty res_ty `thenTc_`
tcMonoExpr expr sig_tc_ty
-- If everything is ok, return the stuff unchanged, except for
-- the effect of any substutions etc. We simply discard the
- -- result of the tcSimplifyAndCheck (inside tcPolyExpr), except for any default
+ -- result of the tcSimplifyCheck (inside tcPolyExpr), except for any default
-- resolution it may have done, which is recorded in the
-- substitution.
returnTc (expr, lie)
\begin{code}
tcMonoExpr (HsWith expr binds) res_ty
- = tcMonoExpr expr res_ty `thenTc` \ (expr', lie) ->
- tcIPBinds binds `thenTc` \ (binds', types, lie2) ->
- partitionPredsOfLIE isBound lie `thenTc` \ (ips, lie', dict_binds) ->
- let expr'' = if nullMonoBinds dict_binds
- then expr'
- else HsLet (mkMonoBind (revBinds dict_binds) [] NonRecursive)
- expr'
- in
- tcCheckIPBinds binds' types ips `thenTc_`
- returnTc (HsWith expr'' binds', lie' `plusLIE` lie2)
- where isBound p
- = case ipName_maybe p of
- Just n -> n `elem` names
- Nothing -> False
- names = map fst binds
- -- revBinds is used because tcSimplify outputs the bindings
- -- out-of-order. it's not a problem elsewhere because these
- -- bindings are normally used in a recursive let
- -- ZZ probably need to find a better solution
- revBinds (b1 `AndMonoBinds` b2) =
- (revBinds b2) `AndMonoBinds` (revBinds b1)
- revBinds b = b
-
-tcIPBinds ((name, expr) : binds)
- = newTyVarTy openTypeKind `thenTc` \ ty ->
- tcGetSrcLoc `thenTc` \ loc ->
- let id = ipToId name ty loc in
- tcMonoExpr expr ty `thenTc` \ (expr', lie) ->
- zonkTcType ty `thenTc` \ ty' ->
- tcIPBinds binds `thenTc` \ (binds', types, lie2) ->
- returnTc ((id, expr') : binds', ty : types, lie `plusLIE` lie2)
-tcIPBinds [] = returnTc ([], [], emptyLIE)
-
-tcCheckIPBinds binds types ips
- = foldrTc tcCheckIPBind (getIPsOfLIE ips) (zip binds types)
-
--- ZZ how do we use the loc?
-tcCheckIPBind bt@((v, _), t1) ((n, t2) : ips) | getName v == n
- = unifyTauTy t1 t2 `thenTc_`
- tcCheckIPBind bt ips `thenTc` \ ips' ->
- returnTc ips'
-tcCheckIPBind bt (ip : ips)
- = tcCheckIPBind bt ips `thenTc` \ ips' ->
- returnTc (ip : ips')
-tcCheckIPBind bt []
- = returnTc []
-\end{code}
+ = tcMonoExpr expr res_ty `thenTc` \ (expr', expr_lie) ->
+ mapAndUnzipTc tcIPBind binds `thenTc` \ (pairs, bind_lies) ->
-Typecheck expression which in most cases will be an Id.
-
-\begin{code}
-tcExpr_id :: RenamedHsExpr
- -> TcM (TcExpr,
- LIE,
- TcType)
-tcExpr_id id_expr
- = case id_expr of
- HsVar name -> tcId name `thenNF_Tc` \ stuff ->
- returnTc stuff
- other -> newTyVarTy openTypeKind `thenNF_Tc` \ id_ty ->
- tcMonoExpr id_expr id_ty `thenTc` \ (id_expr', lie_id) ->
- returnTc (id_expr', lie_id, id_ty)
+ -- If the binding binds ?x = E, we must now
+ -- discharge any ?x constraints in expr_lie
+ tcSimplifyIPs (map fst pairs) expr_lie `thenTc` \ (expr_lie', dict_binds) ->
+ let
+ binds' = [(instToId ip, rhs) | (ip,rhs) <- pairs]
+ expr'' = HsLet (mkMonoBind dict_binds [] Recursive) expr'
+ in
+ returnTc (HsWith expr'' binds', expr_lie' `plusLIE` plusLIEs bind_lies)
+
+tcIPBind (name, expr)
+ = newTyVarTy openTypeKind `thenTc` \ ty ->
+ tcGetSrcLoc `thenTc` \ loc ->
+ newIPDict (IPBind name) name ty `thenNF_Tc` \ ip ->
+ tcMonoExpr expr ty `thenTc` \ (expr', lie) ->
+ returnTc ((ip, expr'), lie)
\end{code}
%************************************************************************
let
(env1, exp_ty'') = tidyOpenType tidy_env exp_ty'
(env2, act_ty'') = tidyOpenType env1 act_ty'
- (exp_args, _) = splitFunTys exp_ty''
- (act_args, _) = splitFunTys act_ty''
+ (exp_args, _) = tcSplitFunTys exp_ty''
+ (act_args, _) = tcSplitFunTys act_ty''
message | length exp_args < length act_args = wrongArgsCtxt "too few" fun args
| length exp_args > length act_args = wrongArgsCtxt "too many" fun args
\begin{code}
tcId :: Name -> NF_TcM (TcExpr, LIE, TcType)
+tcId name -- Look up the Id and instantiate its type
+ = tcLookupId name `thenNF_Tc` \ id ->
+ tcInstId id
+\end{code}
-tcId name
- = -- Look up the Id and instantiate its type
- tcLookup name `thenNF_Tc` \ thing ->
- case thing of
- ATcId tc_id -> instantiate_it (OccurrenceOf tc_id) tc_id (idType tc_id)
- AGlobal (AnId id) -> tcInstId id `thenNF_Tc` \ (tyvars, theta, tau) ->
- instantiate_it2 (OccurrenceOf id) id tyvars theta tau
- where
- -- The instantiate_it loop runs round instantiating the Id.
- -- It has to be a loop because we are now prepared to entertain
- -- types like
- -- f:: forall a. Eq a => forall b. Baz b => tau
- -- We want to instantiate this to
- -- f2::tau {f2 = f1 b (Baz b), f1 = f a (Eq a)}
- instantiate_it orig fun ty
- = tcInstTcType ty `thenNF_Tc` \ (tyvars, rho) ->
- tcSplitRhoTy rho `thenNF_Tc` \ (theta, tau) ->
- instantiate_it2 orig fun tyvars theta tau
-
- instantiate_it2 orig fun tyvars theta tau
- = if null theta then -- Is it overloaded?
- returnNF_Tc (mkHsTyApp (HsVar fun) arg_tys, emptyLIE, tau)
- else
- -- Yes, it's overloaded
- instOverloadedFun orig fun arg_tys theta tau `thenNF_Tc` \ (fun', lie1) ->
- instantiate_it orig fun' tau `thenNF_Tc` \ (expr, lie2, final_tau) ->
- returnNF_Tc (expr, lie1 `plusLIE` lie2, final_tau)
-
- where
- arg_tys = mkTyVarTys tyvars
+Typecheck expression which in most cases will be an Id.
+
+\begin{code}
+tcExpr_id :: RenamedHsExpr -> TcM (TcExpr, LIE, TcType)
+tcExpr_id (HsVar name) = tcId name
+tcExpr_id expr = newTyVarTy openTypeKind `thenNF_Tc` \ id_ty ->
+ tcMonoExpr expr id_ty `thenTc` \ (expr', lie_id) ->
+ returnTc (expr', lie_id, id_ty)
\end{code}
+
%************************************************************************
%* *
\subsection{@tcDoStmts@ typechecks a {\em list} of do statements}
ASSERT( not (null stmts) )
tcAddSrcLoc src_loc $
- newTyVarTy (mkArrowKind boxedTypeKind boxedTypeKind) `thenNF_Tc` \ m ->
- newTyVarTy boxedTypeKind `thenNF_Tc` \ elt_ty ->
- unifyTauTy res_ty (mkAppTy m elt_ty) `thenTc_`
-
-- If it's a comprehension we're dealing with,
-- force it to be a list comprehension.
-- (as of Haskell 98, monad comprehensions are no more.)
(case do_or_lc of
- ListComp -> unifyListTy res_ty `thenTc_` returnTc ()
- _ -> returnTc ()) `thenTc_`
+ ListComp -> unifyListTy res_ty `thenTc` \ elt_ty ->
+ returnNF_Tc (mkTyConTy listTyCon, (mkListTy, elt_ty))
- tcStmts do_or_lc (mkAppTy m) elt_ty src_loc stmts `thenTc` \ ((stmts', _), stmts_lie) ->
+ _ -> newTyVarTy (mkArrowKind liftedTypeKind liftedTypeKind) `thenNF_Tc` \ m_ty ->
+ newTyVarTy liftedTypeKind `thenNF_Tc` \ elt_ty ->
+ unifyTauTy res_ty (mkAppTy m_ty elt_ty) `thenTc_`
+ returnNF_Tc (m_ty, (mkAppTy m_ty, elt_ty))
+ ) `thenNF_Tc` \ (tc_ty, m_ty) ->
+
+ tcStmts (DoCtxt do_or_lc) m_ty stmts `thenTc` \ (stmts', stmts_lie) ->
-- Build the then and zero methods in case we need them
-- It's important that "then" and "return" appear just once in the final LIE,
tcLookupGlobalId returnMName `thenNF_Tc` \ return_sel_id ->
tcLookupGlobalId thenMName `thenNF_Tc` \ then_sel_id ->
tcLookupGlobalId failMName `thenNF_Tc` \ fail_sel_id ->
- newMethod DoOrigin return_sel_id [m] `thenNF_Tc` \ (return_lie, return_id) ->
- newMethod DoOrigin then_sel_id [m] `thenNF_Tc` \ (then_lie, then_id) ->
- newMethod DoOrigin fail_sel_id [m] `thenNF_Tc` \ (fail_lie, fail_id) ->
+ newMethod DoOrigin return_sel_id [tc_ty] `thenNF_Tc` \ return_inst ->
+ newMethod DoOrigin then_sel_id [tc_ty] `thenNF_Tc` \ then_inst ->
+ newMethod DoOrigin fail_sel_id [tc_ty] `thenNF_Tc` \ fail_inst ->
let
- monad_lie = then_lie `plusLIE` return_lie `plusLIE` fail_lie
+ monad_lie = mkLIE [return_inst, then_inst, fail_inst]
in
- returnTc (HsDoOut do_or_lc stmts' return_id then_id fail_id res_ty src_loc,
+ returnTc (HsDoOut do_or_lc stmts'
+ (instToId return_inst) (instToId then_inst) (instToId fail_inst)
+ res_ty src_loc,
stmts_lie `plusLIE` monad_lie)
\end{code}
where
field_names = map fieldLabelName (dataConFieldLabels data_con)
-missingStrictFields rbinds data_con
- = [ fn | fn <- strict_field_names,
- not (fn `elem` field_names_used)
- ]
- where
- field_names_used = [ field_name | (field_name, _, _) <- rbinds ]
- strict_field_names = mapMaybe isStrict field_info
-
- isStrict (fl, MarkedStrict) = Just (fieldLabelName fl)
- isStrict _ = Nothing
-
- field_info = zip (dataConFieldLabels data_con)
- (dataConStrictMarks data_con)
-
missingFields rbinds data_con
- = [ fn | fn <- non_strict_field_names, not (fn `elem` field_names_used) ]
+ | null field_labels = ([], []) -- Not declared as a record;
+ -- But C{} is still valid
+ | otherwise
+ = (missing_strict_fields, other_missing_fields)
where
- field_names_used = [ field_name | (field_name, _, _) <- rbinds ]
-
- -- missing strict fields have already been flagged as
- -- being so, so leave them out here.
- non_strict_field_names = mapMaybe isn'tStrict field_info
-
- isn'tStrict (fl, MarkedStrict) = Nothing
- isn'tStrict (fl, _) = Just (fieldLabelName fl)
-
- field_info = zip (dataConFieldLabels data_con)
- (dataConStrictMarks data_con)
+ missing_strict_fields
+ = [ fl | (fl, str) <- field_info,
+ isMarkedStrict str,
+ not (fieldLabelName fl `elem` field_names_used)
+ ]
+ other_missing_fields
+ = [ fl | (fl, str) <- field_info,
+ not (isMarkedStrict str),
+ not (fieldLabelName fl `elem` field_names_used)
+ ]
+ field_names_used = [ field_name | (field_name, _, _) <- rbinds ]
+ field_labels = dataConFieldLabels data_con
+
+ field_info = zipEqual "missingFields"
+ field_labels
+ (drop (length ex_theta) (dataConStrictMarks data_con))
+ -- The 'drop' is because dataConStrictMarks
+ -- includes the existential dictionaries
+ (_, _, _, ex_theta, _, _) = dataConSig data_con
\end{code}
%************************************************************************
tcLit :: HsLit -> TcType -> TcM (TcExpr, LIE)
tcLit (HsLitLit s _) res_ty
= tcLookupClass cCallableClassName `thenNF_Tc` \ cCallableClass ->
- newClassDicts (LitLitOrigin (_UNPK_ s))
- [(cCallableClass,[res_ty])] `thenNF_Tc` \ (dicts, _) ->
- returnTc (HsLit (HsLitLit s res_ty), dicts)
+ newDicts (LitLitOrigin (_UNPK_ s))
+ [mkClassPred cCallableClass [res_ty]] `thenNF_Tc` \ dicts ->
+ returnTc (HsLit (HsLitLit s res_ty), mkLIE dicts)
tcLit lit res_ty
= unifyTauTy res_ty (simpleHsLitTy lit) `thenTc_`
Mini-utils:
-\begin{code}
-pp_nest_hang :: String -> SDoc -> SDoc
-pp_nest_hang lbl stuff = nest 2 (hang (text lbl) 4 stuff)
-\end{code}
-
Boring and alphabetical:
\begin{code}
arithSeqCtxt expr
notSelector field
= hsep [quotes (ppr field), ptext SLIT("is not a record selector")]
-missingStrictFieldCon :: Name -> Name -> SDoc
+missingStrictFieldCon :: Name -> FieldLabel -> SDoc
missingStrictFieldCon con field
= hsep [ptext SLIT("Constructor") <+> quotes (ppr con),
ptext SLIT("does not have the required strict field"), quotes (ppr field)]
-missingFieldCon :: Name -> Name -> SDoc
+missingFieldCon :: Name -> FieldLabel -> SDoc
missingFieldCon con field
= hsep [ptext SLIT("Field") <+> quotes (ppr field),
ptext SLIT("is not initialised")]