\section[DsMonad]{@DsMonad@: monadery used in desugaring}
\begin{code}
-#include "HsVersions.h"
-
module DsMonad (
- DsM(..),
+ DsM,
initDs, returnDs, thenDs, andDs, mapDs, listDs,
- mapAndUnzipDs, zipWithDs,
+ mapAndUnzipDs, zipWithDs, foldlDs,
uniqSMtoDsM,
newTyVarsDs, cloneTyVarsDs,
duplicateLocalDs, newSysLocalDs, newSysLocalsDs,
newFailLocalDs,
getSrcLocDs, putSrcLocDs,
- getModuleAndGroupDs,
- extendEnvDs, lookupEnvDs, lookupEnvWithDefaultDs,
- DsIdEnv(..),
- lookupId,
+ getModuleAndGroupDs, getUniqueDs,
+ extendEnvDs, lookupEnvDs,
+ DsIdEnv,
- dsShadowError,
+ dsWarn,
+ DsWarnings,
DsMatchContext(..), DsMatchKind(..), pprDsWarnings
) where
-import Ubiq
+#include "HsVersions.h"
-import Bag ( emptyBag, snocBag, bagToList )
-import CmdLineOpts ( opt_SccGroup )
-import CoreSyn ( CoreExpr(..) )
-import CoreUtils ( substCoreExpr )
+import Bag ( emptyBag, snocBag, bagToList, Bag )
+import BasicTypes ( Module )
+import ErrUtils ( WarnMsg )
import HsSyn ( OutPat )
-import Id ( mkSysLocal, mkIdWithNewUniq,
- lookupIdEnv, growIdEnvList, GenId, IdEnv(..)
+import MkId ( mkSysLocal )
+import Id ( mkIdWithNewUniq,
+ lookupIdEnv, growIdEnvList, IdEnv, Id
)
-import PprType ( GenType, GenTyVar )
-import PprStyle ( PprStyle(..) )
-import Pretty
-import SrcLoc ( unpackSrcLoc, mkUnknownSrcLoc, SrcLoc )
-import TcHsSyn ( TypecheckedPat(..) )
-import TyVar ( nullTyVarEnv, cloneTyVar, GenTyVar{-instance Eq-} )
-import Unique ( Unique{-instances-} )
+import Outputable
+import SrcLoc ( noSrcLoc, SrcLoc )
+import TcHsSyn ( TypecheckedPat )
+import Type ( Type )
+import TyVar ( cloneTyVar, TyVar )
import UniqSupply ( splitUniqSupply, getUnique, getUniques,
- mapUs, thenUs, returnUs, UniqSM(..) )
-import Util ( assoc, mapAccumL, zipWithEqual, panic )
+ UniqSM, UniqSupply )
+import Unique ( Unique )
+import Util ( zipWithEqual, panic )
infixr 9 `thenDs`
\end{code}
\begin{code}
type DsM result =
UniqSupply
- -> SrcLoc -- to put in pattern-matching error msgs
- -> (FAST_STRING, FAST_STRING) -- "module"+"group" : for SCC profiling
+ -> 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 WarnMsg -- The desugarer reports matches which are
+ -- completely shadowed or incomplete patterns
+
+type Group = FAST_STRING
+
{-# INLINE andDs #-}
{-# INLINE thenDs #-}
{-# INLINE returnDs #-}
initDs :: UniqSupply
-> DsIdEnv
- -> 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 mod_name action
- = action init_us mkUnknownSrcLoc module_and_group env emptyBag
- where
- module_and_group = (mod_name, grp_name)
- grp_name = case opt_SccGroup of
- Just xx -> 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
mapDs f xs `thenDs` \ rs ->
returnDs (r:rs)
+foldlDs :: (a -> b -> DsM a) -> a -> [b] -> DsM a
+
+foldlDs k z [] = returnDs z
+foldlDs k z (x:xs) = k z x `thenDs` \ r ->
+ foldlDs k r xs
+
+
mapAndUnzipDs :: (a -> DsM (b, c)) -> [a] -> DsM ([b], [c])
mapAndUnzipDs f [] = 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 ->
returnDs (r:rs)
--- Note: crashes if lists not equal length (like zipWithEqual)
\end{code}
And all this mysterious stuff is so we can occasionally reach out and
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 -> Type -> DsM Id
newLocalDs nm ty us loc mod_and_grp env warns
newSysLocalsDs tys = mapDs (newLocalDs SLIT("ds")) tys
newFailLocalDs = newLocalDs SLIT("fail")
+getUniqueDs :: DsM Unique
+getUniqueDs us loc mod_and_grp env warns
+ = case (getUnique us) of { assigned_uniq ->
+ (assigned_uniq, warns) }
+
duplicateLocalDs :: Id -> DsM Id
duplicateLocalDs old_local us loc mod_and_grp env warns
= case (getUnique us) of { assigned_uniq ->
cloneTyVarsDs :: [TyVar] -> DsM [TyVar]
cloneTyVarsDs tyvars us loc mod_and_grp env warns
= case (getUniques (length tyvars) us) of { uniqs ->
- (zipWithEqual cloneTyVar tyvars uniqs, warns) }
+ (zipWithEqual "cloneTyVarsDs" cloneTyVar tyvars uniqs, warns) }
\end{code}
\begin{code}
newTyVarsDs tyvar_tmpls us loc mod_and_grp env warns
= case (getUniques (length tyvar_tmpls) us) of { uniqs ->
- (zipWithEqual cloneTyVar tyvar_tmpls uniqs, warns) }
+ (zipWithEqual "newTyVarsDs" cloneTyVar tyvar_tmpls uniqs, warns) }
\end{code}
We can also reach out and either set/grab location information from
uniqSMtoDsM u_action us loc mod_and_grp env warns
= (u_action us, warns)
-getSrcLocDs :: DsM (String, String)
+getSrcLocDs :: DsM SrcLoc
getSrcLocDs us loc mod_and_grp env warns
- = case (unpackSrcLoc loc) of { (x,y) ->
- ((_UNPK_ x, _UNPK_ y), warns) }
+ = (loc, warns)
putSrcLocDs :: SrcLoc -> DsM a -> DsM a
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 mod_and_grp env warns
- = ((), warns `snocBag` cxt)
+dsWarn :: WarnMsg -> DsM ()
+dsWarn warn us loc mod_and_grp env warns = ((), warns `snocBag` warn)
+
\end{code}
\begin{code}
\end{code}
\begin{code}
-type DsIdEnv = IdEnv CoreExpr
+type DsIdEnv = IdEnv Id
-extendEnvDs :: [(Id, CoreExpr)] -> DsM a -> DsM a
+extendEnvDs :: [(Id, Id)] -> DsM a -> DsM a
extendEnvDs pairs then_do us loc mod_and_grp old_env warns
- = case splitUniqSupply us of { (s1, s2) ->
- let
- revised_pairs = subst_all pairs s1
- in
- then_do s2 loc mod_and_grp (growIdEnvList old_env revised_pairs) warns
- }
- where
- subst_all pairs = mapUs subst pairs
-
- subst (v, expr)
- = substCoreExpr old_env nullTyVarEnv expr `thenUs` \ new_expr ->
- returnUs (v, new_expr)
-
-lookupEnvDs :: Id -> DsM (Maybe CoreExpr)
-lookupEnvDs id us loc 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)
+ = then_do us loc mod_and_grp (growIdEnvList old_env pairs) warns
-lookupEnvWithDefaultDs :: Id -> CoreExpr -> DsM CoreExpr
-lookupEnvWithDefaultDs id deflt us loc mod_and_grp env 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}
%************************************************************************
data DsMatchContext
= DsMatchContext DsMatchKind [TypecheckedPat] SrcLoc
| NoMatchContext
+ deriving ()
data DsMatchKind
= FunMatch Id
| CaseMatch
| LambdaMatch
| PatBindMatch
+ | DoBindMatch
+ | ListCompMatch
+ | LetMatch
+ deriving ()
-pprDsWarnings :: PprStyle -> Bag DsMatchContext -> Pretty
-pprDsWarnings sty warns
- = ppAboves (map pp_cxt (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:"))
- 4 (pp_match kind pats))
-
- pp_match (FunMatch fun) pats
- = ppHang (ppr sty fun)
- 4 (ppSep [ppSep (map (ppr sty) pats), ppPStr SLIT("= ...")])
-
- pp_match CaseMatch pats
- = ppHang (ppPStr SLIT("in a case alternative:"))
- 4 (ppSep [ppSep (map (ppr sty) pats), pp_arrow_dotdotdot])
-
- pp_match PatBindMatch pats
- = ppHang (ppPStr SLIT("in a pattern binding:"))
- 4 (ppSep [ppSep (map (ppr sty) pats), pp_arrow_dotdotdot])
-
- pp_match LambdaMatch pats
- = ppHang (ppPStr SLIT("in a lambda abstraction:"))
- 4 (ppSep [ppSep (map (ppr sty) pats), pp_arrow_dotdotdot])
-
- pp_arrow_dotdotdot = ppPStr SLIT("-> ...")
+pprDsWarnings :: DsWarnings -> SDoc
+pprDsWarnings warns = vcat (bagToList warns)
\end{code}
projects / ghc-hetmet.git / blobdiff