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,
23 import Bag ( Bag, emptyBag, snocBag, unionBags )
24 import CmdLineOpts ( opt_CompilingPrelude )
25 import ErrUtils ( addShortErrLocLine )
26 import FiniteMap ( FiniteMap, emptyFM, isEmptyFM,
27 lookupFM, addListToFM, addToFM )
28 import Maybes ( maybeToBool )
29 import Name ( RdrName(..), isQual, pprNonSym, getLocalName, ExportFlag(..) )
30 import PprStyle ( PprStyle(..) )
32 import RnHsSyn ( RnName )
33 import Util ( assertPanic )
36 *********************************************************
38 \subsection{RnEnv: renaming environment}
40 *********************************************************
42 Separate FiniteMaps are kept for lookup up Qual names,
43 Unqual names and Local names.
46 type RnEnv = ((QualNames, UnqualNames, QualNames, UnqualNames), ScopeStack)
48 type QualNames = FiniteMap (FAST_STRING,Module) RnName
49 type UnqualNames = FiniteMap FAST_STRING RnName
50 type ScopeStack = FiniteMap FAST_STRING RnName
53 extendGlobalRnEnv :: RnEnv -> [(RdrName,RnName)] -> [(RdrName,RnName)]
54 -> (RnEnv, Bag (RdrName, RnName, RnName))
55 extendLocalRnEnv :: Bool -> RnEnv -> [RnName] -> (RnEnv, [RnName])
56 lookupRnEnv :: RnEnv -> RdrName -> Maybe RnName
57 lookupGlobalRnEnv :: RnEnv -> RdrName -> Maybe RnName
58 lookupTcRnEnv :: RnEnv -> RdrName -> Maybe RnName
61 If the @RdrName@ is a @Qual@, @lookupValue@ looks it up in the global
62 value QualNames. If it is @Unqual@, it looks it up first in the
63 ScopeStack, and if it isn't found there, then in the global
66 @lookupTcRnEnv@ looks up tycons/classes in the alternative global
69 @extendGlobalRnEnv@ adds global names to the RnEnv. It takes separate
70 value and tycon/class name lists. It returns any duplicate names
73 @extendRnEnv@ adds new local names to the ScopeStack in an RnEnv.
74 It optionally reports any shadowed names.
78 = ((emptyFM, emptyFM, emptyFM, emptyFM), emptyFM)
80 extendGlobalRnEnv ((qual, unqual, tc_qual, tc_unqual), stack) val_list tc_list
81 = ASSERT(isEmptyFM stack)
82 (((qual', unqual', tc_qual', tc_unqual'), stack), tc_dups `unionBags` dups)
84 (qual', unqual', dups) = extend_global qual unqual val_list
85 (tc_qual', tc_unqual', tc_dups) = extend_global tc_qual tc_unqual tc_list
87 extend_global qual unqual rdr_list = (qual', unqual', dups)
89 (qual_list, unqual_list) = partition (isQual.fst) rdr_list
90 qual_in = map mk_qual qual_list
91 unqual_in = map mk_unqual unqual_list
92 mk_qual (Qual m s, rn) = ((s,m), rn)
93 mk_unqual (Unqual s, rn) = (s, rn)
95 (qual', qual_dups) = do_dups qual_in qual emptyBag (\ (s,m) -> Qual m s)
96 (unqual', unqual_dups) = do_dups unqual_in unqual emptyBag Unqual
98 dups = unqual_dups `unionBags` qual_dups
100 do_dups [] fm dups to_rdr = (fm, dups)
101 do_dups ((k,v):rest) fm dups to_rdr
102 = case lookupFM fm k of
103 Nothing -> do_dups rest (addToFM fm k v) dups to_rdr
104 Just cur -> do_dups rest fm (dups `snocBag` (to_rdr k, cur, v)) to_rdr
107 extendLocalRnEnv report_shadows (global, stack) new_local
108 = ((global, new_stack), dups)
110 (new_stack, dups) = extend new_local stack
113 = if report_shadows then
114 do_shadows names stack []
116 (addListToFM stack [ (getLocalName n, n) | n <- names], [])
118 do_shadows [] stack dups = (stack, dups)
119 do_shadows (name:names) stack dups
120 = do_shadows names (addToFM stack str name) ext_dups
122 str = getLocalName name
123 ext_dups = if maybeToBool (lookupFM stack str)
128 lookupRnEnv ((qual, unqual, _, _), stack) rdr
130 Unqual str -> lookup stack str (lookup unqual str Nothing)
131 Qual mod str -> lookup qual (str,mod)
132 (if not opt_CompilingPrelude -- see below
134 else lookup unqual str Nothing)
136 lookup fm thing do_on_fail
137 = case lookupFM fm thing of
138 found@(Just name) -> found
139 Nothing -> do_on_fail
141 lookupGlobalRnEnv ((qual, unqual, _, _), _) rdr
143 Unqual str -> lookupFM unqual str
144 Qual mod str -> case (lookupFM qual (str,mod)) of
146 Nothing -> if not opt_CompilingPrelude then
148 else -- "[]" may have turned into "Prelude.[]" and
149 -- we are actually compiling "data [] a = ...";
150 -- maybe the right thing is to get "Prelude.[]"
151 -- into the "qual" table...
154 lookupTcRnEnv ((_, _, tc_qual, tc_unqual), _) rdr
156 Unqual str -> lookupFM tc_unqual str
157 Qual mod str -> case (lookupFM tc_qual (str,mod)) of -- as above
159 Nothing -> if not opt_CompilingPrelude then
162 lookupFM tc_unqual str
165 *********************************************************
167 \subsection{Export Flag Functions}
169 *********************************************************
172 lubExportFlag ExportAll ExportAll = ExportAll
173 lubExportFlag ExportAll ExportAbs = ExportAll
174 lubExportFlag ExportAbs ExportAll = ExportAll
175 lubExportFlag ExportAbs ExportAbs = ExportAbs
178 *********************************************************
180 \subsection{Errors used *more than once* in the renamer}
182 *********************************************************
185 qualNameErr descriptor (name,locn)
186 = addShortErrLocLine locn ( \ sty ->
187 ppBesides [ppStr "invalid use of qualified ", ppStr descriptor, ppStr ": ", pprNonSym sty name ] )
189 dupNamesErr descriptor ((name1,locn1) : dup_things) sty
190 = ppAboves (item1 : map dup_item dup_things)
193 = addShortErrLocLine locn1 (\ sty ->
194 ppBesides [ppStr "multiple declarations of a ", ppStr descriptor, ppStr " `",
195 pprNonSym sty name1, ppStr "'" ]) sty
197 dup_item (name, locn)
198 = addShortErrLocLine locn (\ sty ->
199 ppBesides [ppStr "here was another declaration of `",
200 pprNonSym sty name, ppStr "'" ]) sty