2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
4 \section[RnUtils]{Functions used by both renaming passes}
7 #include "HsVersions.h"
10 RnEnv(..), QualNames(..),
11 UnqualNames(..), ScopeStack(..),
12 emptyRnEnv, extendGlobalRnEnv, extendLocalRnEnv,
13 lookupRnEnv, lookupGlobalRnEnv, lookupTcRnEnv,
28 import Bag ( Bag, emptyBag, snocBag, unionBags )
29 import ErrUtils ( addShortErrLocLine, addShortWarnLocLine, addErrLoc )
30 import FiniteMap ( FiniteMap, emptyFM, isEmptyFM,
31 lookupFM, addListToFM, addToFM )
32 import Maybes ( maybeToBool )
33 import Name ( RdrName(..), isQual, pprNonSym, getLocalName, ExportFlag(..) )
34 import PprStyle ( PprStyle(..) )
36 import RnHsSyn ( RnName )
37 import Util ( assertPanic )
40 *********************************************************
42 \subsection{RnEnv: renaming environment}
44 *********************************************************
46 Seperate FiniteMaps are kept for lookup up Qual names,
47 Unqual names and Local names.
50 type RnEnv = ((QualNames, UnqualNames, QualNames, UnqualNames), ScopeStack)
52 type QualNames = FiniteMap (FAST_STRING,Module) RnName
53 type UnqualNames = FiniteMap FAST_STRING RnName
54 type ScopeStack = FiniteMap FAST_STRING RnName
57 extendGlobalRnEnv :: RnEnv -> [(RdrName,RnName)] -> [(RdrName,RnName)]
58 -> (RnEnv, Bag (RdrName, RnName, RnName))
59 extendLocalRnEnv :: Bool -> RnEnv -> [RnName] -> (RnEnv, [RnName])
60 lookupRnEnv :: RnEnv -> RdrName -> Maybe RnName
61 lookupGlobalRnEnv :: RnEnv -> RdrName -> Maybe RnName
62 lookupTcRnEnv :: RnEnv -> RdrName -> Maybe RnName
65 If the @RdrName@ is a @Qual@, @lookupValue@ looks it up in the global
66 value QualNames. If it is @Unqual@, it looks it up first in the
67 ScopeStack, and if it isn't found there, then in the global
70 @lookupTcRnEnv@ looks up tycons/classes in the alternative global
73 @extendGlobalRnEnv@ adds global names to the RnEnv. It takes separate
74 value and tycon/class name lists. It returns any duplicate names
77 @extendRnEnv@ adds new local names to the ScopeStack in an RnEnv.
78 It optionally reports any shadowed names.
82 = ((emptyFM, emptyFM, emptyFM, emptyFM), emptyFM)
84 extendGlobalRnEnv ((qual, unqual, tc_qual, tc_unqual), stack) val_list tc_list
85 = ASSERT(isEmptyFM stack)
86 (((qual', unqual', tc_qual', tc_unqual'), stack), tc_dups `unionBags` dups)
88 (qual', unqual', dups) = extend_global qual unqual val_list
89 (tc_qual', tc_unqual', tc_dups) = extend_global tc_qual tc_unqual tc_list
91 extend_global qual unqual rdr_list = (qual', unqual', dups)
93 (qual_list, unqual_list) = partition (isQual.fst) rdr_list
94 qual_in = map mk_qual qual_list
95 unqual_in = map mk_unqual unqual_list
96 mk_qual (Qual m s, rn) = ((s,m), rn)
97 mk_unqual (Unqual s, rn) = (s, rn)
99 (qual', qual_dups) = do_dups qual_in qual emptyBag (\ (s,m) -> Qual m s)
100 (unqual', unqual_dups) = do_dups unqual_in unqual emptyBag Unqual
102 dups = unqual_dups `unionBags` qual_dups
104 do_dups [] fm dups to_rdr = (fm, dups)
105 do_dups ((k,v):rest) fm dups to_rdr
106 = case lookupFM fm k of
107 Nothing -> do_dups rest (addToFM fm k v) dups to_rdr
108 Just cur -> do_dups rest fm (dups `snocBag` (to_rdr k, cur, v)) to_rdr
111 extendLocalRnEnv report_shadows (global, stack) new_local
112 = ((global, new_stack), dups)
114 (new_stack, dups) = extend new_local stack
117 = if report_shadows then
118 do_shadows names stack []
120 (addListToFM stack [ (getLocalName n, n) | n <- names], [])
122 do_shadows [] stack dups = (stack, dups)
123 do_shadows (name:names) stack dups
124 = do_shadows names (addToFM stack str name) ext_dups
126 str = getLocalName name
127 ext_dups = if maybeToBool (lookupFM stack str)
132 lookupRnEnv ((qual, unqual, _, _), stack) rdr
134 Unqual str -> lookup stack str (lookup unqual str Nothing)
135 Qual mod str -> lookup qual (str,mod) Nothing
137 lookup fm thing do_on_fail
138 = case lookupFM fm thing of
139 found@(Just name) -> found
140 Nothing -> do_on_fail
142 lookupGlobalRnEnv ((qual, unqual, _, _), _) rdr
144 Unqual str -> lookupFM unqual str
145 Qual mod str -> lookupFM qual (str,mod)
147 lookupTcRnEnv ((_, _, tc_qual, tc_unqual), _) rdr
149 Unqual str -> lookupFM tc_unqual str
150 Qual mod str -> lookupFM tc_qual (str,mod)
153 *********************************************************
155 \subsection{Export Flag Functions}
157 *********************************************************
160 lubExportFlag ExportAll ExportAll = ExportAll
161 lubExportFlag ExportAll ExportAbs = ExportAll
162 lubExportFlag ExportAbs ExportAll = ExportAll
163 lubExportFlag ExportAbs ExportAbs = ExportAbs
166 *********************************************************
168 \subsection{Errors used in RnMonad}
170 *********************************************************
173 unknownNameErr descriptor name locn
174 = addShortErrLocLine locn ( \ sty ->
175 ppBesides [ppStr "undefined ", ppStr descriptor, ppStr ": ", pprNonSym sty name] )
177 badClassOpErr clas op locn
178 = addErrLoc locn "" ( \ sty ->
179 ppBesides [ppChar '`', pprNonSym sty op, ppStr "' is not an operation of class `",
180 ppr sty clas, ppStr "'"] )
182 qualNameErr descriptor (name,locn)
183 = addShortErrLocLine locn ( \ sty ->
184 ppBesides [ppStr "invalid use of qualified ", ppStr descriptor, ppStr ": ", pprNonSym sty name ] )
186 dupNamesErr descriptor ((name1,locn1) : dup_things) sty
187 = ppAboves (item1 : map dup_item dup_things)
190 = addShortErrLocLine locn1 (\ sty ->
191 ppBesides [ppStr "multiple declarations of a ", ppStr descriptor, ppStr " `",
192 pprNonSym sty name1, ppStr "'" ]) sty
194 dup_item (name, locn)
195 = addShortErrLocLine locn (\ sty ->
196 ppBesides [ppStr "here was another declaration of `",
197 pprNonSym sty name, ppStr "'" ]) sty
199 shadowedNameWarn locn shadow
200 = addShortWarnLocLine locn ( \ sty ->
201 ppBesides [ppStr "more than one value with the same name (shadowing): ", ppr sty shadow] )
203 multipleOccWarn (name, occs) sty
204 = ppBesides [ppStr "warning:multiple names used to refer to `", ppr sty name, ppStr "': ",
205 ppInterleave ppComma (map (ppr sty) occs)]
207 negateNameWarn (name,locn)
208 = addShortWarnLocLine locn ( \ sty ->
209 ppBesides [ppStr "local binding of `negate' will be used for prefix `-'"])