%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1995
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
%
-\section[DesugarMonad]{@DesugarMonad@: monadery used in desugaring}
+\section[DsMonad]{@DsMonad@: monadery used in desugaring}
\begin{code}
#include "HsVersions.h"
module DsMonad (
- DsM(..),
+ SYN_IE(DsM),
initDs, returnDs, thenDs, andDs, mapDs, listDs,
mapAndUnzipDs, zipWithDs,
uniqSMtoDsM,
duplicateLocalDs, newSysLocalDs, newSysLocalsDs,
newFailLocalDs,
getSrcLocDs, putSrcLocDs,
- getSwitchCheckerDs, ifSwitchSetDs,
getModuleAndGroupDs,
- extendEnvDs, lookupEnvDs, lookupEnvWithDefaultDs,
- DsIdEnv(..),
- lookupId,
+ extendEnvDs, lookupEnvDs,
+ SYN_IE(DsIdEnv),
- dsShadowError,
+ dsShadowWarn, dsIncompleteWarn,
+ SYN_IE(DsWarnings),
DsMatchContext(..), DsMatchKind(..), pprDsWarnings,
+ DsWarnFlavour -- Nuke with 1.4
-#ifdef DPH
- listDs,
-#endif
-
- -- and to make the interface self-sufficient...
- Id, DataCon(..), SrcLoc, TyVar, TyVarTemplate, UniType, TauType(..),
- ThetaType(..), SigmaType(..), SplitUniqSupply, UniqSM(..),
- PlainCoreExpr(..), CoreExpr, GlobalSwitch, SwitchResult
-
- IF_ATTACK_PRAGMAS(COMMA lookupUFM COMMA lookupIdEnv)
- IF_ATTACK_PRAGMAS(COMMA mkIdWithNewUniq COMMA mkSysLocal)
- IF_ATTACK_PRAGMAS(COMMA unpackSrcLoc COMMA mkUniqueSupplyGrimily)
- IF_ATTACK_PRAGMAS(COMMA mkUniqueGrimily)
- IF_ATTACK_PRAGMAS(COMMA splitUniqSupply COMMA getSUnique)
) where
-import AbsSyn
-import AbsUniType ( cloneTyVarFromTemplate, cloneTyVar,
- TyVar, TyVarTemplate, UniType, TauType(..),
- ThetaType(..), SigmaType(..), Class
- IF_ATTACK_PRAGMAS(COMMA cmpTyVar)
+IMP_Ubiq()
+
+import Bag ( emptyBag, snocBag, bagToList, Bag )
+import BasicTypes ( SYN_IE(Module) )
+import CmdLineOpts ( opt_PprUserLength )
+import CoreSyn ( SYN_IE(CoreExpr) )
+import CoreUtils ( substCoreExpr )
+import HsSyn ( OutPat )
+import Id ( mkSysLocal, mkIdWithNewUniq,
+ lookupIdEnv, growIdEnvList, GenId, SYN_IE(IdEnv),
+ SYN_IE(Id)
)
-import Bag
-import CmdLineOpts -- ( GlobalSwitch(..), SwitchResult(..), switchIsOn )
-import Id ( mkIdWithNewUniq, mkSysLocal, Id, DataCon(..) )
-import IdEnv -- ( mkIdEnv, IdEnv )
-import Maybes ( assocMaybe, Maybe(..) )
-import Outputable
-import PlainCore
+import PprType ( GenType, GenTyVar )
+import Outputable ( pprQuote, Outputable(..), PprStyle(..) )
import Pretty
-import SrcLoc ( unpackSrcLoc, mkUnknownSrcLoc, SrcLoc )
-import TyVarEnv -- ( nullTyVarEnv, TyVarEnv )
-import SplitUniq
-import Unique
-import Util
+import SrcLoc ( noSrcLoc, SrcLoc )
+import TcHsSyn ( SYN_IE(TypecheckedPat) )
+import Type ( SYN_IE(Type) )
+import TyVar ( nullTyVarEnv, cloneTyVar, GenTyVar{-instance Eq-}, SYN_IE(TyVar) )
+import Unique ( Unique{-instances-} )
+import UniqSupply ( splitUniqSupply, getUnique, getUniques,
+ mapUs, thenUs, returnUs, SYN_IE(UniqSM),
+ UniqSupply )
+import Util ( assoc, mapAccumL, zipWithEqual, panic )
infixr 9 `thenDs`
\end{code}
presumably include source-file location information:
\begin{code}
type DsM result =
- SplitUniqSupply
- -> SrcLoc -- to put in pattern-matching error msgs
- -> (GlobalSwitch -> SwitchResult) -- so we can consult global switches
- -> (FAST_STRING, FAST_STRING) -- "module"+"group" : for SCC profiling
+ UniqSupply
+ -> SrcLoc -- to put in pattern-matching error msgs
+ -> (Module, Group) -- module + group name : for SCC profiling
-> DsIdEnv
-> DsWarnings
-> (result, DsWarnings)
-type DsWarnings = Bag DsMatchContext -- The desugarer reports matches which are
- -- completely shadowed
+type DsWarnings = Bag (DsWarnFlavour, DsMatchContext)
+ -- The desugarer reports matches which are
+ -- completely shadowed or incomplete patterns
+
+type Group = FAST_STRING
-#ifdef __GLASGOW_HASKELL__
{-# INLINE andDs #-}
{-# INLINE thenDs #-}
{-# INLINE returnDs #-}
-#endif
-- initDs returns the UniqSupply out the end (not just the result)
-initDs :: SplitUniqSupply
+initDs :: UniqSupply
-> DsIdEnv
- -> (GlobalSwitch -> SwitchResult)
- -> FAST_STRING -- module name: for profiling; (group name: from switches)
+ -> (Module, Group) -- module name: for profiling; (group name: from switches)
-> DsM a
-> (a, DsWarnings)
-initDs init_us env sw_chkr mod_name action
- = action init_us mkUnknownSrcLoc sw_chkr module_and_group env emptyBag
- where
- module_and_group = (mod_name, grp_name)
- grp_name = case (stringSwitchSet sw_chkr SccGroup) of
- Just xx -> _PK_ xx
- Nothing -> mod_name -- default: module name
+initDs init_us env module_and_group action
+ = action init_us noSrcLoc module_and_group env emptyBag
thenDs :: DsM a -> (a -> DsM b) -> DsM b
andDs :: (a -> a -> a) -> DsM a -> DsM a -> DsM a
-thenDs expr cont us loc sw_chkr mod_and_grp env warns
- = case splitUniqSupply us of { (s1, s2) ->
- case (expr s1 loc sw_chkr mod_and_grp env warns) of { (result, warns1) ->
- cont result s2 loc sw_chkr mod_and_grp env warns1}}
+thenDs m1 m2 us loc mod_and_grp env warns
+ = case splitUniqSupply us of { (s1, s2) ->
+ case (m1 s1 loc mod_and_grp env warns) of { (result, warns1) ->
+ m2 result s2 loc mod_and_grp env warns1}}
-andDs combiner m1 m2 us loc sw_chkr mod_and_grp env warns
- = case splitUniqSupply us of { (s1, s2) ->
- case (m1 s1 loc sw_chkr mod_and_grp env warns) of { (result1, warns1) ->
- case (m2 s2 loc sw_chkr mod_and_grp env warns1) of { (result2, warns2) ->
+andDs combiner m1 m2 us loc mod_and_grp env warns
+ = case splitUniqSupply us of { (s1, s2) ->
+ case (m1 s1 loc mod_and_grp env warns) of { (result1, warns1) ->
+ case (m2 s2 loc mod_and_grp env warns1) of { (result2, warns2) ->
(combiner result1 result2, warns2) }}}
returnDs :: a -> DsM a
-returnDs result us loc sw_chkr mod_and_grp env warns = (result, warns)
+returnDs result us loc mod_and_grp env warns = (result, warns)
listDs :: [DsM a] -> DsM [a]
listDs [] = returnDs []
zipWithDs :: (a -> b -> DsM c) -> [a] -> [b] -> DsM [c]
-zipWithDs f [] [] = returnDs []
+zipWithDs f [] ys = returnDs []
zipWithDs f (x:xs) (y:ys)
= f x y `thenDs` \ r ->
zipWithDs f xs ys `thenDs` \ rs ->
grab one or more names. @newLocalDs@ isn't exported---exported
functions are defined with it. The difference in name-strings makes
it easier to read debugging output.
+
\begin{code}
-newLocalDs :: FAST_STRING -> UniType -> DsM Id
-newLocalDs nm ty us loc sw_chkr mod_and_grp env warns
- = case (getSUnique us) of { assigned_uniq ->
+newLocalDs :: FAST_STRING -> Type -> DsM Id
+newLocalDs nm ty us loc mod_and_grp env warns
+ = case (getUnique us) of { assigned_uniq ->
(mkSysLocal nm assigned_uniq ty loc, warns) }
newSysLocalDs = newLocalDs SLIT("ds")
newFailLocalDs = newLocalDs SLIT("fail")
duplicateLocalDs :: Id -> DsM Id
-duplicateLocalDs old_local us loc sw_chkr mod_and_grp env warns
- = case (getSUnique us) of { assigned_uniq ->
+duplicateLocalDs old_local us loc mod_and_grp env warns
+ = case (getUnique us) of { assigned_uniq ->
(mkIdWithNewUniq old_local assigned_uniq, warns) }
cloneTyVarsDs :: [TyVar] -> DsM [TyVar]
-cloneTyVarsDs tyvars us loc sw_chkr mod_and_grp env warns
- = case (getSUniques (length tyvars) us) of { uniqs ->
- (zipWith cloneTyVar tyvars uniqs, warns) }
+cloneTyVarsDs tyvars us loc mod_and_grp env warns
+ = case (getUniques (length tyvars) us) of { uniqs ->
+ (zipWithEqual "cloneTyVarsDs" cloneTyVar tyvars uniqs, warns) }
\end{code}
\begin{code}
-newTyVarsDs :: [TyVarTemplate] -> DsM [TyVar]
+newTyVarsDs :: [TyVar] -> DsM [TyVar]
-newTyVarsDs tyvar_tmpls us loc sw_chkr mod_and_grp env warns
- = case (getSUniques (length tyvar_tmpls) us) of { uniqs ->
- (zipWith cloneTyVarFromTemplate tyvar_tmpls uniqs, warns) }
+newTyVarsDs tyvar_tmpls us loc mod_and_grp env warns
+ = case (getUniques (length tyvar_tmpls) us) of { uniqs ->
+ (zipWithEqual "newTyVarsDs" cloneTyVar tyvar_tmpls uniqs, warns) }
\end{code}
We can also reach out and either set/grab location information from
\begin{code}
uniqSMtoDsM :: UniqSM a -> DsM a
-uniqSMtoDsM u_action us loc sw_chkr mod_and_grp env warns
- = let
- us_to_use = mkUniqueSupplyGrimily us
- in
- (snd (u_action us_to_use), warns)
+uniqSMtoDsM u_action us loc mod_and_grp env warns
+ = (u_action us, warns)
-getSrcLocDs :: DsM (String, String)
-getSrcLocDs us loc sw_chkr mod_and_grp env warns
- = case (unpackSrcLoc loc) of { (x,y) ->
- ((_UNPK_ x, _UNPK_ y), warns) }
+getSrcLocDs :: DsM SrcLoc
+getSrcLocDs us loc mod_and_grp env warns
+ = (loc, warns)
putSrcLocDs :: SrcLoc -> DsM a -> DsM a
-putSrcLocDs new_loc expr us old_loc sw_chkr mod_and_grp env warns
- = expr us new_loc sw_chkr mod_and_grp env warns
+putSrcLocDs new_loc expr us old_loc mod_and_grp env warns
+ = expr us new_loc mod_and_grp env warns
-dsShadowError :: DsMatchContext -> DsM ()
-dsShadowError cxt us loc sw_chkr mod_and_grp env warns
- = ((), warns `snocBag` cxt)
+dsShadowWarn :: DsMatchContext -> DsM ()
+dsShadowWarn cxt us loc mod_and_grp env warns
+ = ((), warns `snocBag` (Shadowed, cxt))
+
+dsIncompleteWarn :: DsMatchContext -> DsM ()
+dsIncompleteWarn cxt us loc mod_and_grp env warns
+ = ((), warns `snocBag` (Incomplete, cxt))
\end{code}
\begin{code}
-getSwitchCheckerDs :: DsM (GlobalSwitch -> Bool)
-getSwitchCheckerDs us loc sw_chkr mod_and_grp env warns
- = (switchIsOn sw_chkr, warns)
-
-ifSwitchSetDs :: GlobalSwitch -> DsM a -> DsM a -> DsM a
-ifSwitchSetDs switch then_ else_ us loc sw_chkr mod_and_grp env warns
- = (if switchIsOn sw_chkr switch then then_ else else_)
- us loc sw_chkr mod_and_grp env warns
-
getModuleAndGroupDs :: DsM (FAST_STRING, FAST_STRING)
-getModuleAndGroupDs us loc sw_chkr mod_and_grp env warns
+getModuleAndGroupDs us loc mod_and_grp env warns
= (mod_and_grp, warns)
\end{code}
\begin{code}
-type DsIdEnv = IdEnv PlainCoreExpr
+type DsIdEnv = IdEnv Id
-extendEnvDs :: [(Id, PlainCoreExpr)] -> DsM a -> DsM a
+extendEnvDs :: [(Id, Id)] -> DsM a -> DsM a
-extendEnvDs pairs expr us loc sw_chkr mod_and_grp old_env warns
- = case splitUniqSupply us of { (s1, s2) ->
- case (mapAccumL subst s1 pairs) of { (_, revised_pairs) ->
- expr s2 loc sw_chkr mod_and_grp (growIdEnvList old_env revised_pairs) warns
- }}
- where
- subst us (v, expr)
- = case splitUniqSupply us of { (s1, s2) ->
- let
- us_to_use = mkUniqueSupplyGrimily s1
- in
- case (substCoreExpr us_to_use old_env nullTyVarEnv expr) of { (_, expr2) ->
- (s2, (v, expr2)) }}
-
-lookupEnvDs :: Id -> DsM (Maybe PlainCoreExpr)
-lookupEnvDs id us loc sw_chkr mod_and_grp env warns
- = (lookupIdEnv env id, warns)
- -- Note: we don't assert anything about the Id
- -- being looked up. There's not really anything
- -- much to say about it. (WDP 94/06)
-
-lookupEnvWithDefaultDs :: Id -> PlainCoreExpr -> DsM PlainCoreExpr
-lookupEnvWithDefaultDs id deflt us loc sw_chkr mod_and_grp env warns
+extendEnvDs pairs then_do us loc mod_and_grp old_env warns
+ = then_do us loc mod_and_grp (growIdEnvList old_env pairs) warns
+
+lookupEnvDs :: Id -> DsM Id
+lookupEnvDs id us loc mod_and_grp env warns
= (case (lookupIdEnv env id) of
- Nothing -> deflt
+ Nothing -> id
Just xx -> xx,
warns)
-
-lookupId :: [(Id, a)] -> Id -> a
-lookupId env id
- = assoc "lookupId" env id
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
+data DsWarnFlavour = Shadowed | Incomplete deriving ()
+
data DsMatchContext
= DsMatchContext DsMatchKind [TypecheckedPat] SrcLoc
| NoMatchContext
+ deriving ()
data DsMatchKind
= FunMatch Id
| CaseMatch
| LambdaMatch
| PatBindMatch
+ | DoBindMatch
+ deriving ()
-pprDsWarnings :: PprStyle -> Bag DsMatchContext -> Pretty
+pprDsWarnings :: PprStyle -> DsWarnings -> Doc
pprDsWarnings sty warns
- = ppAboves (map pp_cxt (bagToList warns))
+ = vcat (map pp_warn (bagToList warns))
where
- pp_cxt NoMatchContext = ppPStr SLIT("Some match is shadowed; I don't know what")
- pp_cxt (DsMatchContext kind pats loc)
- = ppHang (ppBesides [ppr PprForUser loc, ppPStr SLIT(": ")])
- 4 (ppHang (ppPStr SLIT("Pattern match(es) completely overlapped:"))
+ pp_warn (flavour, NoMatchContext) = sep [ptext SLIT("Warning: Some match is"),
+ case flavour of
+ Shadowed -> ptext SLIT("shadowed")
+ Incomplete -> ptext SLIT("possibly incomplete")]
+
+ pp_warn (flavour, DsMatchContext kind pats loc)
+ = hang (hcat [ppr (PprForUser opt_PprUserLength) loc, ptext SLIT(": ")])
+ 4 (hang msg
4 (pp_match kind pats))
+ where
+ msg = case flavour of
+ Shadowed -> ptext SLIT("Warning: Pattern match(es) completely overlapped")
+ Incomplete -> ptext SLIT("Warning: Possibly incomplete patterns")
pp_match (FunMatch fun) pats
- = ppHang (ppr sty fun)
- 4 (ppSep [ppSep (map (ppr sty) pats), ppPStr SLIT("= ...")])
+ = hsep [ptext SLIT("in the definition of function"), ppr sty fun]
pp_match CaseMatch pats
- = ppHang (ppPStr SLIT("in a case alternative:"))
- 4 (ppSep [ppSep (map (ppr sty) pats), pp_arrow_dotdotdot])
+ = hang (ptext SLIT("in a group of case alternatives beginning:"))
+ 4 (ppr_pats pats)
pp_match PatBindMatch pats
- = ppHang (ppPStr SLIT("in a pattern binding:"))
- 4 (ppSep [ppSep (map (ppr sty) pats), pp_arrow_dotdotdot])
+ = hang (ptext SLIT("in a pattern binding:"))
+ 4 (ppr_pats pats)
pp_match LambdaMatch pats
- = ppHang (ppPStr SLIT("in a lambda abstraction:"))
- 4 (ppSep [ppSep (map (ppr sty) pats), pp_arrow_dotdotdot])
+ = hang (ptext SLIT("in a lambda abstraction:"))
+ 4 (ppr_pats pats)
+
+ pp_match DoBindMatch pats
+ = hang (ptext SLIT("in a `do' pattern binding:"))
+ 4 (ppr_pats pats)
- pp_arrow_dotdotdot = ppPStr SLIT("-> ...")
+ ppr_pats pats = pprQuote sty $ \ sty ->
+ sep [sep (map (ppr sty) pats), ptext SLIT("-> ...")]
\end{code}