-- NOTE: accept -} at the end of a LINE pragma, for compatibility
-- with older versions of GHC which generated these.
--- We only want RULES pragmas to be picked up when explicit forall
--- syntax is enabled is on, because the contents of the pragma always
--- uses it. If it's not on then we're sure to get a parse error.
--- (ToDo: we should really emit a warning when ignoring pragmas)
--- XXX Now that we can enable this without the -fglasgow-exts hammer,
--- is it better just to let the parse error happen?
-<0>
- "{-#" $whitechar* (RULES|rules) / { ifExtension explicitForallEnabled } { token ITrules_prag }
-
<0,option_prags> {
+ "{-#" $whitechar* (RULES|rules) { token ITrules_prag }
"{-#" $whitechar* (INLINE|inline) { token (ITinline_prag True) }
"{-#" $whitechar* (NO(T?)INLINE|no(t?)inline)
{ token (ITinline_prag False) }
{ nested_comment lexToken }
-- ToDo: should only be valid inside a pragma:
- "#-}" { token ITclose_prag}
+ "#-}" { endPrag }
}
<option_prags> {
( "where", ITwhere, 0 ),
( "_scc_", ITscc, 0 ), -- ToDo: remove
- ( "forall", ITforall, bit explicitForallBit),
+ ( "forall", ITforall, bit explicitForallBit .|. bit inRulePragBit),
( "mdo", ITmdo, bit recursiveDoBit),
( "family", ITfamily, bit tyFamBit),
( "group", ITgroup, bit transformComprehensionsBit),
-- For data T (a::*) = MkT
,("*", ITstar, \i -> kindSigsEnabled i || tyFamEnabled i)
-- For 'forall a . t'
- ,(".", ITdot, explicitForallEnabled)
+ ,(".", ITdot, \i -> explicitForallEnabled i || inRulePrag i)
,("-<", ITlarrowtail, arrowsEnabled)
,(">-", ITrarrowtail, arrowsEnabled)
Just (_, _) -> lexDocComment input (ITdocSection n) True
Nothing -> do setInput input; lexToken -- eof reached, lex it normally
+-- RULES pragmas turn on the forall and '.' keywords, and we turn them
+-- off again at the end of the pragma.
+rulePrag :: Action
+rulePrag span buf len = do
+ setExts (.|. inRulePragBit)
+ return (L span ITrules_prag)
+
+endPrag :: Action
+endPrag span buf len = do
+ setExts (.&. complement (bit inRulePragBit))
+ return (L span ITclose_prag)
+
-- docCommentEnd
-------------------------------------------------------------------------------
-- This function is quite tricky. We can't just return a new token, we also
getExts :: P Int
getExts = P $ \s -> POk s (extsBitmap s)
+setExts :: (Int -> Int) -> P ()
+setExts f = P $ \s -> POk s{ extsBitmap = f (extsBitmap s) } ()
+
setSrcLoc :: SrcLoc -> P ()
setSrcLoc new_loc = P $ \s -> POk s{loc=new_loc} ()
standaloneDerivingBit = 16 -- standalone instance deriving declarations
transformComprehensionsBit = 17
qqBit = 18 -- enable quasiquoting
+inRulePragBit = 19
genericsEnabled, ffiEnabled, parrEnabled :: Int -> Bool
always _ = True
standaloneDerivingEnabled flags = testBit flags standaloneDerivingBit
transformComprehensionsEnabled flags = testBit flags transformComprehensionsBit
qqEnabled flags = testBit flags qqBit
+inRulePrag flags = testBit flags inRulePragBit
-- PState for parsing options pragmas
--
.|. qqBit `setBitIf` dopt Opt_QuasiQuotes flags
.|. ipBit `setBitIf` dopt Opt_ImplicitParams flags
.|. explicitForallBit `setBitIf` dopt Opt_ScopedTypeVariables flags
+ .|. explicitForallBit `setBitIf` dopt Opt_LiberalTypeSynonyms flags
.|. explicitForallBit `setBitIf` dopt Opt_PolymorphicComponents flags
.|. explicitForallBit `setBitIf` dopt Opt_ExistentialQuantification flags
.|. explicitForallBit `setBitIf` dopt Opt_Rank2Types flags