import Name
import TyCon
import Type
+import TypeRep
import Coercion
import Var
import VarSet
%************************************************************************
\begin{code}
+
+updHetMetLevel :: ([TyVar] -> [TyVar]) -> TcM a -> TcM a
+updHetMetLevel f comp =
+ updEnv
+ (\oldenv -> let oldlev = (case oldenv of Env { env_lcl = e' } -> case e' of TcLclEnv { tcl_hetMetLevel = x } -> x)
+ in (oldenv { env_lcl = (env_lcl oldenv) { tcl_hetMetLevel = f oldlev } }))
+
+ comp
+
+addEscapes :: [TyVar] -> HsExpr Name -> HsExpr Name
+addEscapes [] e = e
+addEscapes (t:ts) e = HsHetMetEsc (TyVarTy t) placeHolderType (noLoc (addEscapes ts e))
+
+getIdLevel :: Name -> TcM [TyVar]
+getIdLevel name
+ = do { thing <- tcLookup name
+ ; case thing of
+ ATcId { tct_hetMetLevel = variable_hetMetLevel } -> return $ variable_hetMetLevel
+ _ -> return []
+ }
+
tcExpr :: HsExpr Name -> TcRhoType -> TcM (HsExpr TcId)
tcExpr e res_ty | debugIsOn && isSigmaTy res_ty -- Sanity check
= pprPanic "tcExpr: sigma" (ppr res_ty $$ ppr e)
tcExpr (HsVar name) res_ty = tcCheckId name res_ty
-tcExpr (HsApp e1 e2) res_ty = tcApp e1 [e2] res_ty
+tcExpr (HsHetMetBrak _ e) res_ty =
+ do { (coi, [inferred_name,elt_ty]) <- matchExpectedTyConApp hetMetCodeTypeTyCon res_ty
+ ; fresh_ec_name <- newFlexiTyVar ecKind
+ ; expr' <- updHetMetLevel (\old_lev -> (fresh_ec_name:old_lev))
+ $ tcPolyExpr e elt_ty
+ ; unifyType (TyVarTy fresh_ec_name) inferred_name
+ ; return $ mkHsWrapCoI coi (HsHetMetBrak (TyVarTy fresh_ec_name) expr') }
+tcExpr (HsHetMetEsc _ _ e) res_ty =
+ do { cur_level <- getHetMetLevel
+ ; expr' <- updHetMetLevel (\old_lev -> tail old_lev)
+ $ tcExpr (unLoc e) (mkTyConApp hetMetCodeTypeTyCon [(TyVarTy $ head cur_level),res_ty])
+ ; ty' <- zonkTcType res_ty
+ ; return $ mkHsWrapCoI (ACo res_ty) (HsHetMetEsc (TyVarTy $ head cur_level) ty' (noLoc expr')) }
+tcExpr (HsHetMetCSP _ e) res_ty =
+ do { cur_level <- getHetMetLevel
+ ; expr' <- updHetMetLevel (\old_lev -> tail old_lev)
+ $ tcExpr (unLoc e) res_ty
+ ; return $ mkHsWrapCoI (ACo res_ty) (HsHetMetCSP (TyVarTy $ head cur_level) (noLoc expr')) }
-tcExpr (HsLit lit) res_ty = do { let lit_ty = hsLitType lit
- ; tcWrapResult (HsLit lit) lit_ty res_ty }
+tcExpr (HsApp e1 e2) res_ty = tcApp e1 [e2] res_ty
+tcExpr (HsLit lit) res_ty =
+ getHetMetLevel >>= \lev ->
+ case lev of
+ [] -> do { let lit_ty = hsLitType lit
+ ; tcWrapResult (HsLit lit) lit_ty res_ty }
+ (ec:rest) -> let n = case lit of
+ (HsChar c) -> hetmet_guest_char_literal_name
+ (HsString str) -> hetmet_guest_string_literal_name
+ (HsInteger i _) -> hetmet_guest_integer_literal_name
+ (HsInt i) -> hetmet_guest_integer_literal_name
+ _ -> error "literals of this sort are not allowed at depth >0"
+ in tcExpr (HsHetMetEsc (TyVarTy ec) placeHolderType $ noLoc $
+ (HsApp (noLoc $ HsVar n) (noLoc $ HsLit lit))) res_ty
+
tcExpr (HsPar expr) res_ty = do { expr' <- tcMonoExprNC expr res_ty
; return (HsPar expr') }
= do { expr' <- tcMonoExpr expr res_ty
; return (HsCoreAnn lbl expr') }
-tcExpr (HsOverLit lit) res_ty
- = do { lit' <- newOverloadedLit (LiteralOrigin lit) lit res_ty
- ; return (HsOverLit lit') }
+tcExpr (HsOverLit lit) res_ty =
+ getHetMetLevel >>= \lev ->
+ case lev of
+ [] -> do { lit' <- newOverloadedLit (LiteralOrigin lit) lit res_ty
+ ; return (HsOverLit lit') }
+ (ec:rest) -> let n = case lit of
+ (OverLit { ol_val = HsIntegral i }) -> hetmet_guest_integer_literal_name
+ (OverLit { ol_val = HsIsString fs }) -> hetmet_guest_string_literal_name
+ (OverLit { ol_val = HsFractional f }) -> error "fractional literals not allowed at depth >0"
+ in tcExpr (HsHetMetEsc (TyVarTy ec) placeHolderType $ noLoc $
+ (HsApp (noLoc $ HsVar n) (noLoc $ HsOverLit lit))) res_ty
+
tcExpr (NegApp expr neg_expr) res_ty
= do { neg_expr' <- tcSyntaxOp NegateOrigin neg_expr
tcInferIdWithOrig :: CtOrigin -> Name -> TcM (HsExpr TcId, TcRhoType)
-- Look up an occurrence of an Id, and instantiate it (deeply)
-tcInferIdWithOrig orig id_name
- = do { id <- lookup_id
- ; (id_expr, id_rho) <- instantiateOuter orig id
- ; (wrap, rho) <- deeplyInstantiate orig id_rho
- ; return (mkHsWrap wrap id_expr, rho) }
+tcInferIdWithOrig orig id_name =
+ do { id_level <- getIdLevel id_name
+ ; cur_level <- getHetMetLevel
+ ; if (length id_level < length cur_level)
+ then do { (lhexp, tcrho) <-
+ tcInferRho (noLoc $ addEscapes (take ((length cur_level) - (length id_level)) cur_level) (HsVar id_name))
+ ; return (unLoc lhexp, tcrho)
+ }
+ else tcInferIdWithOrig' orig id_name
+ }
+
+tcInferIdWithOrig' orig id_name =
+ do { id <- lookup_id
+ ; (id_expr, id_rho) <- instantiateOuter orig id
+ ; (wrap, rho) <- deeplyInstantiate orig id_rho
+ ; return (mkHsWrap wrap id_expr, rho) }
where
lookup_id :: TcM TcId
lookup_id
= do { thing <- tcLookup id_name
; case thing of
- ATcId { tct_id = id, tct_level = lvl }
+ ATcId { tct_id = id, tct_level = lvl, tct_hetMetLevel = variable_hetMetLevel }
-> do { check_naughty id -- Note [Local record selectors]
; checkThLocalId id lvl
+ ; current_hetMetLevel <- getHetMetLevel
+ ; mapM
+ (\(name1,name2) -> unifyType (TyVarTy name1) (TyVarTy name2))
+ (zip variable_hetMetLevel current_hetMetLevel)
; return id }
AGlobal (AnId id)
- -> do { check_naughty id; return id }
- -- A global cannot possibly be ill-staged
+ -> do { check_naughty id
+ ; return id }
+ -- A global cannot possibly be ill-staged in Template Haskell
-- nor does it need the 'lifting' treatment
-- hence no checkTh stuff here