X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fparser%2FLexer.x;h=4e9617602280fe2cf5dac5fb4b032e3fdf9124b1;hp=3a001bd08eeeb341c47c9f5e36c309e9488985cf;hb=b017f34bebf1588e5e579d7c653413e2a4c2d170;hpb=a3a7bba7445be24db313f89eb558b3c0fd55ed6e diff --git a/compiler/parser/Lexer.x b/compiler/parser/Lexer.x index 3a001bd..4e96176 100644 --- a/compiler/parser/Lexer.x +++ b/compiler/parser/Lexer.x @@ -51,7 +51,7 @@ module Lexer ( getMessages, popContext, pushCurrentContext, setLastToken, setSrcLoc, getLexState, popLexState, pushLexState, - extension, standaloneDerivingEnabled, bangPatEnabled, + extension, bangPatEnabled, addWarning, lexTokenStream ) where @@ -701,7 +701,6 @@ reservedSymsFM = listToUFM $ explicitForallEnabled i) ,("→", ITrarrow, unicodeSyntaxEnabled) ,("←", ITlarrow, unicodeSyntaxEnabled) - ,("⋯", ITdotdot, unicodeSyntaxEnabled) ,("⤙", ITlarrowtail, \i -> unicodeSyntaxEnabled i && arrowsEnabled i) ,("⤚", ITrarrowtail, \i -> unicodeSyntaxEnabled i && arrowsEnabled i) @@ -1736,8 +1735,6 @@ unicodeSyntaxBit :: Int unicodeSyntaxBit = 14 -- the forall symbol, arrow symbols, etc unboxedTuplesBit :: Int unboxedTuplesBit = 15 -- (# and #) -standaloneDerivingBit :: Int -standaloneDerivingBit = 16 -- standalone instance deriving declarations transformComprehensionsBit :: Int transformComprehensionsBit = 17 qqBit :: Int @@ -1781,8 +1778,6 @@ unicodeSyntaxEnabled :: Int -> Bool unicodeSyntaxEnabled flags = testBit flags unicodeSyntaxBit unboxedTuplesEnabled :: Int -> Bool unboxedTuplesEnabled flags = testBit flags unboxedTuplesBit -standaloneDerivingEnabled :: Int -> Bool -standaloneDerivingEnabled flags = testBit flags standaloneDerivingBit qqEnabled :: Int -> Bool qqEnabled flags = testBit flags qqBit -- inRulePrag :: Int -> Bool @@ -1821,8 +1816,8 @@ pragState dynflags buf loc = -- create a parse state -- -mkPState :: StringBuffer -> SrcLoc -> DynFlags -> PState -mkPState buf loc flags = +mkPState :: DynFlags -> StringBuffer -> SrcLoc -> PState +mkPState flags buf loc = PState { buffer = buf, dflags = flags, @@ -1833,7 +1828,6 @@ mkPState buf loc flags = extsBitmap = fromIntegral bitmap, context = [], lex_state = [bol, 0], - -- we begin in the layout state if toplev_layout is set alr_pending_implicit_tokens = [], alr_next_token = Nothing, alr_last_loc = noSrcSpan, @@ -1860,7 +1854,6 @@ mkPState buf loc flags = .|. recBit `setBitIf` dopt Opt_Arrows flags .|. unicodeSyntaxBit `setBitIf` dopt Opt_UnicodeSyntax flags .|. unboxedTuplesBit `setBitIf` dopt Opt_UnboxedTuples flags - .|. standaloneDerivingBit `setBitIf` dopt Opt_StandaloneDeriving flags .|. transformComprehensionsBit `setBitIf` dopt Opt_TransformListComp flags .|. rawTokenStreamBit `setBitIf` dopt Opt_KeepRawTokenStream flags .|. newQualOpsBit `setBitIf` dopt Opt_NewQualifiedOperators flags @@ -1981,7 +1974,9 @@ alternativeLayoutRuleToken t mExpectingOCurly <- getAlrExpectingOCurly justClosedExplicitLetBlock <- getJustClosedExplicitLetBlock setJustClosedExplicitLetBlock False - let thisLoc = getLoc t + dflags <- getDynFlags + let transitional = dopt Opt_AlternativeLayoutRuleTransitional dflags + thisLoc = getLoc t thisCol = srcSpanStartCol thisLoc newLine = (lastLoc == noSrcSpan) || (srcSpanStartLine thisLoc > srcSpanEndLine lastLoc) @@ -2040,6 +2035,30 @@ alternativeLayoutRuleToken t do setPendingImplicitTokens [t] setALRContext ls return (L thisLoc ITccurly) + -- This next case is to handle a transitional issue: + (ITwhere, ALRLayout _ col : ls, _) + | newLine && thisCol == col && transitional -> + do addWarning Opt_WarnAlternativeLayoutRuleTransitional + thisLoc + (transitionalAlternativeLayoutWarning + "`where' clause at the same depth as implicit layout block") + setALRContext ls + setNextToken t + -- Note that we use lastLoc, as we may need to close + -- more layouts, or give a semicolon + return (L lastLoc ITccurly) + -- This next case is to handle a transitional issue: + (ITvbar, ALRLayout _ col : ls, _) + | newLine && thisCol == col && transitional -> + do addWarning Opt_WarnAlternativeLayoutRuleTransitional + thisLoc + (transitionalAlternativeLayoutWarning + "`|' at the same depth as implicit layout block") + setALRContext ls + setNextToken t + -- Note that we use lastLoc, as we may need to close + -- more layouts, or give a semicolon + return (L lastLoc ITccurly) (_, ALRLayout _ col : ls, _) | newLine && thisCol == col -> do setNextToken t @@ -2050,10 +2069,8 @@ alternativeLayoutRuleToken t -- Note that we use lastLoc, as we may need to close -- more layouts, or give a semicolon return (L lastLoc ITccurly) - (u, _, _) - | isALRopen u -> - do setALRContext (ALRNoLayout (containsCommas u) False : context) - return t + -- We need to handle close before open, as 'then' is both + -- an open and a close (u, _, _) | isALRclose u -> case context of @@ -2062,13 +2079,24 @@ alternativeLayoutRuleToken t setNextToken t return (L thisLoc ITccurly) ALRNoLayout _ isLet : ls -> - do setALRContext ls + do let ls' = if isALRopen u + then ALRNoLayout (containsCommas u) False : ls + else ls + setALRContext ls' when isLet $ setJustClosedExplicitLetBlock True return t [] -> - -- XXX This is an error in John's code, but - -- it looks reachable to me at first glance - return t + do let ls = if isALRopen u + then [ALRNoLayout (containsCommas u) False] + else ls + setALRContext ls + -- XXX This is an error in John's code, but + -- it looks reachable to me at first glance + return t + (u, _, _) + | isALRopen u -> + do setALRContext (ALRNoLayout (containsCommas u) False : context) + return t (ITin, ALRLayout ALRLayoutLet _ : ls, _) -> do setALRContext ls setPendingImplicitTokens [t] @@ -2090,9 +2118,15 @@ alternativeLayoutRuleToken t -- the other ITwhere case omitted; general case below covers it (_, _, _) -> return t +transitionalAlternativeLayoutWarning :: String -> SDoc +transitionalAlternativeLayoutWarning msg + = text "transitional layout will not be accepted in the future:" + $$ text msg + isALRopen :: Token -> Bool isALRopen ITcase = True isALRopen ITif = True +isALRopen ITthen = True isALRopen IToparen = True isALRopen ITobrack = True isALRopen ITocurly = True @@ -2104,6 +2138,7 @@ isALRopen _ = False isALRclose :: Token -> Bool isALRclose ITof = True isALRclose ITthen = True +isALRclose ITelse = True isALRclose ITcparen = True isALRclose ITcbrack = True isALRclose ITccurly = True @@ -2166,7 +2201,8 @@ reportLexError loc1 loc2 buf str lexTokenStream :: StringBuffer -> SrcLoc -> DynFlags -> ParseResult [Located Token] lexTokenStream buf loc dflags = unP go initState - where initState = mkPState buf loc (dopt_set (dopt_unset dflags Opt_Haddock) Opt_KeepRawTokenStream) + where dflags' = dopt_set (dopt_unset dflags Opt_Haddock) Opt_KeepRawTokenStream + initState = mkPState dflags' buf loc go = do ltok <- lexer return case ltok of