X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Fparser%2FLexer.x;h=e83bf944b6e54ed7cb833fd955bb3608e36e7cc6;hb=81d2f8a9de4b6f17ca5ee00d984c07fecc98f67f;hp=ccfc3e850592f91c387414d9ab54beeb1e9b8454;hpb=98744cef7b82e7eefbb1c6f1d8b9e28c415939c4;p=ghc-hetmet.git diff --git a/ghc/compiler/parser/Lexer.x b/ghc/compiler/parser/Lexer.x index ccfc3e8..e83bf94 100644 --- a/ghc/compiler/parser/Lexer.x +++ b/ghc/compiler/parser/Lexer.x @@ -22,15 +22,14 @@ { module Lexer ( - Token(..), Token__(..), lexer, mkPState, showPFailed, - P(..), ParseResult(..), setSrcLocFor, getSrcLoc, - failLocMsgP, srcParseFail, + Token(..), lexer, mkPState, + P(..), ParseResult(..), getSrcLoc, + failMsgP, failLocMsgP, failSpanMsgP, srcParseFail, popContext, pushCurrentContext, ) where #include "HsVersions.h" -import ForeignCall ( Safety(..) ) import ErrUtils ( Message ) import Outputable import StringBuffer @@ -45,7 +44,7 @@ import Util ( maybePrefixMatch ) import DATA_BITS import Char import Ratio -import TRACE +--import TRACE } $whitechar = [\ \t\n\r\f\v\xa0] @@ -160,7 +159,9 @@ $white_no_nl+ ; -- {-# LINE "" #-} $digit+ { set_line line_prag2a } \" [$graphic \ ]* \" { set_file line_prag2b } - "#-}" { pop } + "#-}"|"-}" { pop } + -- NOTE: accept -} at the end of a LINE pragma, for compatibility + -- with older versions of GHC which generated these. <0,glaexts> { "{-#" $whitechar* (SPECIALI[SZ]E|speciali[sz]e) @@ -174,6 +175,7 @@ $white_no_nl+ ; { token ITdeprecated_prag } "{-#" $whitechar* (SCC|scc) { token ITscc_prag } "{-#" $whitechar* (CORE|core) { token ITcore_prag } + "{-#" $whitechar* (UNPACK|unpack) { token ITunpack_prag } "{-#" { nested_comment } @@ -298,9 +300,7 @@ unsafeAt arr i = arr ! i -- ----------------------------------------------------------------------------- -- The token type -data Token = T SrcLoc{-start-} SrcLoc{-end-} Token__ - -data Token__ +data Token = ITas -- Haskell keywords | ITcase | ITclass @@ -349,6 +349,7 @@ data Token__ | ITline_prag | ITscc_prag | ITcore_prag -- hdaume: core annotations + | ITunpack_prag | ITclose_prag | ITdotdot -- reserved symbols @@ -440,7 +441,7 @@ data Token__ deriving Show -- debugging #endif -isSpecial :: Token__ -> Bool +isSpecial :: Token -> Bool -- If we see M.x, where x is a keyword, but -- is special, we treat is as just plain M.x, -- not as a keyword. @@ -542,39 +543,39 @@ reservedSymsFM = listToUFM $ -- ----------------------------------------------------------------------------- -- Lexer actions -type Action = SrcLoc -> SrcLoc -> StringBuffer -> Int -> P Token +type Action = SrcSpan -> StringBuffer -> Int -> P (Located Token) -special :: Token__ -> Action -special tok loc end _buf len = return (T loc end tok) +special :: Token -> Action +special tok span _buf len = return (L span tok) -token, layout_token :: Token__ -> Action -token t loc end buf len = return (T loc end t) -layout_token t loc end buf len = pushLexState layout >> return (T loc end t) +token, layout_token :: Token -> Action +token t span buf len = return (L span t) +layout_token t span buf len = pushLexState layout >> return (L span t) -idtoken :: (StringBuffer -> Int -> Token__) -> Action -idtoken f loc end buf len = return (T loc end $! (f buf len)) +idtoken :: (StringBuffer -> Int -> Token) -> Action +idtoken f span buf len = return (L span $! (f buf len)) -skip_one_varid :: (FastString -> Token__) -> Action -skip_one_varid f loc end buf len - = return (T loc end $! f (lexemeToFastString (stepOn buf) (len-1))) +skip_one_varid :: (FastString -> Token) -> Action +skip_one_varid f span buf len + = return (L span $! f (lexemeToFastString (stepOn buf) (len-1))) -strtoken :: (String -> Token__) -> Action -strtoken f loc end buf len = - return (T loc end $! (f $! lexemeToString buf len)) +strtoken :: (String -> Token) -> Action +strtoken f span buf len = + return (L span $! (f $! lexemeToString buf len)) -init_strtoken :: Int -> (String -> Token__) -> Action +init_strtoken :: Int -> (String -> Token) -> Action -- like strtoken, but drops the last N character(s) -init_strtoken drop f loc end buf len = - return (T loc end $! (f $! lexemeToString buf (len-drop))) +init_strtoken drop f span buf len = + return (L span $! (f $! lexemeToString buf (len-drop))) begin :: Int -> Action -begin code _loc _end _str _len = do pushLexState code; lexToken +begin code _span _str _len = do pushLexState code; lexToken pop :: Action -pop _loc _end _buf _len = do popLexState; lexToken +pop _span _buf _len = do popLexState; lexToken pop_and :: Action -> Action -pop_and act loc end buf len = do popLexState; act loc end buf len +pop_and act span buf len = do popLexState; act span buf len notFollowedBy char _ _ _ (_,buf) = atEnd buf || currentChar buf /= char @@ -588,7 +589,7 @@ ifExtension pred bits _ _ _ = pred bits using regular expressions. -} nested_comment :: Action -nested_comment loc _end _str _len = do +nested_comment span _str _len = do input <- getInput go 1 input where go 0 input = do setInput input; lexToken @@ -609,21 +610,22 @@ nested_comment loc _end _str _len = do Just (c,input) -> go n input c -> go n input - err input = do failLocMsgP loc (fst input) "unterminated `{-'" + err input = do failLocMsgP (srcSpanStart span) (fst input) + "unterminated `{-'" open_brace, close_brace :: Action -open_brace loc end _str _len = do +open_brace span _str _len = do ctx <- getContext setContext (NoLayout:ctx) - return (T loc end ITocurly) -close_brace loc end _str _len = do + return (L span ITocurly) +close_brace span _str _len = do popContext - return (T loc end ITccurly) + return (L span ITccurly) -- We have to be careful not to count M. as a qualified name -- when is a keyword. We hack around this by catching -- the offending tokens afterward, and re-lexing in a different state. -check_qvarid loc end buf len = do +check_qvarid span buf len = do case lookupUFM reservedWordsFM var of Just (keyword,exts) | not (isSpecial keyword) -> @@ -636,10 +638,10 @@ check_qvarid loc end buf len = do _other -> return token where (mod,var) = splitQualName buf len - token = T loc end (ITqvarid (mod,var)) + token = L span (ITqvarid (mod,var)) try_again = do - setInput (loc,buf) + setInput (srcSpanStart span,buf) pushLexState bad_qvarid lexToken @@ -668,17 +670,17 @@ splitQualName orig_buf len = split orig_buf 0 0 (lexemeToFastString orig_buf dot_off, lexemeToFastString (stepOnBy (dot_off+1) orig_buf) (len - dot_off -1)) -varid loc end buf len = +varid span buf len = case lookupUFM reservedWordsFM fs of Just (keyword,0) -> do maybe_layout keyword - return (T loc end keyword) + return (L span keyword) Just (keyword,exts) -> do b <- extension (\i -> exts .&. i /= 0) if b then do maybe_layout keyword - return (T loc end keyword) - else return (T loc end (ITvarid fs)) - _other -> return (T loc end (ITvarid fs)) + return (L span keyword) + else return (L span (ITvarid fs)) + _other -> return (L span (ITvarid fs)) where fs = lexemeToFastString buf len @@ -691,34 +693,34 @@ qconsym buf len = ITqconsym $! splitQualName buf len varsym = sym ITvarsym consym = sym ITconsym -sym con loc end buf len = +sym con span buf len = case lookupUFM reservedSymsFM fs of - Just (keyword,0) -> return (T loc end keyword) + Just (keyword,0) -> return (L span keyword) Just (keyword,exts) -> do b <- extension (\i -> exts .&. i /= 0) - if b then return (T loc end keyword) - else return (T loc end $! con fs) - _other -> return (T loc end $! con fs) + if b then return (L span keyword) + else return (L span $! con fs) + _other -> return (L span $! con fs) where fs = lexemeToFastString buf len -tok_decimal loc end buf len - = return (T loc end (ITinteger $! parseInteger buf len 10 oct_or_dec)) +tok_decimal span buf len + = return (L span (ITinteger $! parseInteger buf len 10 oct_or_dec)) -tok_octal loc end buf len - = return (T loc end (ITinteger $! parseInteger (stepOnBy 2 buf) (len-2) 8 oct_or_dec)) +tok_octal span buf len + = return (L span (ITinteger $! parseInteger (stepOnBy 2 buf) (len-2) 8 oct_or_dec)) -tok_hexadecimal loc end buf len - = return (T loc end (ITinteger $! parseInteger (stepOnBy 2 buf) (len-2) 16 hex)) +tok_hexadecimal span buf len + = return (L span (ITinteger $! parseInteger (stepOnBy 2 buf) (len-2) 16 hex)) -prim_decimal loc end buf len - = return (T loc end (ITprimint $! parseInteger buf (len-1) 10 oct_or_dec)) +prim_decimal span buf len + = return (L span (ITprimint $! parseInteger buf (len-1) 10 oct_or_dec)) -prim_octal loc end buf len - = return (T loc end (ITprimint $! parseInteger (stepOnBy 2 buf) (len-3) 8 oct_or_dec)) +prim_octal span buf len + = return (L span (ITprimint $! parseInteger (stepOnBy 2 buf) (len-3) 8 oct_or_dec)) -prim_hexadecimal loc end buf len - = return (T loc end (ITprimint $! parseInteger (stepOnBy 2 buf) (len-3) 16 hex)) +prim_hexadecimal span buf len + = return (L span (ITprimint $! parseInteger (stepOnBy 2 buf) (len-3) 16 hex)) tok_float str = ITrational $! readRational__ str prim_float str = ITprimfloat $! readRational__ str @@ -735,18 +737,18 @@ parseInteger buf len radix to_int -- we're at the first token on a line, insert layout tokens if necessary do_bol :: Action -do_bol loc end _str _len = do - pos <- getOffside end +do_bol span _str _len = do + pos <- getOffside (srcSpanEnd span) case pos of LT -> do --trace "layout: inserting '}'" $ do popContext -- do NOT pop the lex state, we might have a ';' to insert - return (T loc end ITvccurly) + return (L span ITvccurly) EQ -> do --trace "layout: inserting ';'" $ do popLexState - return (T loc end ITsemi) + return (L span ITsemi) GT -> do popLexState lexToken @@ -770,9 +772,9 @@ maybe_layout _ = return () -- by a 'do', then we allow the new context to be at the same indentation as -- the previous context. This is what the 'strict' argument is for. -- -new_layout_context strict loc end _buf _len = do +new_layout_context strict span _buf _len = do popLexState - let offset = srcLocCol loc + let offset = srcSpanStartCol span ctx <- getContext case ctx of Layout prev_off : _ | @@ -781,32 +783,32 @@ new_layout_context strict loc end _buf _len = do -- token is indented to the left of the previous context. -- we must generate a {} sequence now. pushLexState layout_left - return (T loc end ITvocurly) + return (L span ITvocurly) other -> do setContext (Layout offset : ctx) - return (T loc end ITvocurly) + return (L span ITvocurly) -do_layout_left loc end _buf _len = do +do_layout_left span _buf _len = do popLexState pushLexState bol -- we must be at the start of a line - return (T loc end ITvccurly) + return (L span ITvccurly) -- ----------------------------------------------------------------------------- -- LINE pragmas set_line :: Int -> Action -set_line code loc end buf len = do +set_line code span buf len = do let line = parseInteger buf len 10 oct_or_dec - setSrcLoc (mkSrcLoc (srcLocFile end) (fromIntegral line - 1) 0) + setSrcLoc (mkSrcLoc (srcSpanFile span) (fromIntegral line - 1) 0) -- subtract one: the line number refers to the *following* line popLexState pushLexState code lexToken set_file :: Int -> Action -set_file code loc end buf len = do +set_file code span buf len = do let file = lexemeToFastString (stepOn buf) (len-2) - setSrcLoc (mkSrcLoc file (srcLocLine end) (srcLocCol end)) + setSrcLoc (mkSrcLoc file (srcSpanEndLine span) (srcSpanEndCol span)) popLexState pushLexState code lexToken @@ -817,12 +819,12 @@ set_file code loc end buf len = do -- This stuff is horrible. I hates it. lex_string_tok :: Action -lex_string_tok loc end buf len = do +lex_string_tok span buf len = do tok <- lex_string "" end <- getSrcLoc - return (T loc end tok) + return (L (mkSrcSpan (srcSpanStart span) end) tok) -lex_string :: String -> P Token__ +lex_string :: String -> P Token lex_string s = do i <- getInput case alexGetChar i of @@ -858,14 +860,6 @@ lex_string s = do c <- lex_char lex_string (c:s) -lex_char :: P Char -lex_char = do - mc <- getCharOrFail - case mc of - '\\' -> lex_escape - c | is_any c -> return c - _other -> lit_error - lex_stringgap s = do c <- getCharOrFail case c of @@ -881,8 +875,9 @@ lex_char_tok :: Action -- but WIHTOUT CONSUMING the x or T part (the parser does that). -- So we have to do two characters of lookahead: when we see 'x we need to -- see if there's a trailing quote -lex_char_tok loc _end buf len = do -- We've seen ' +lex_char_tok span buf len = do -- We've seen ' i1 <- getInput -- Look ahead to first character + let loc = srcSpanStart span case alexGetChar i1 of Nothing -> lit_error @@ -890,7 +885,7 @@ lex_char_tok loc _end buf len = do -- We've seen ' th_exts <- extension thEnabled if th_exts then do setInput i2 - return (T loc end2 ITtyQuote) + return (L (mkSrcSpan loc end2) ITtyQuote) else lit_error Just ('\\', i2@(end2,_)) -> do -- We've seen 'backslash @@ -913,23 +908,31 @@ lex_char_tok loc _end buf len = do -- We've seen ' _other -> do -- We've seen 'x not followed by quote -- If TH is on, just parse the quote only th_exts <- extension thEnabled - if th_exts then return (T loc (fst i1) ITvarQuote) + if th_exts then return (L (mkSrcSpan loc (fst i1)) ITvarQuote) else lit_error -finish_char_tok :: SrcLoc -> Char -> P Token +finish_char_tok :: SrcLoc -> Char -> P (Located Token) finish_char_tok loc ch -- We've already seen the closing quote -- Just need to check for trailing # = do glaexts <- extension glaExtsEnabled + i@(end,_) <- getInput if glaexts then do - i@(end,_) <- getInput case alexGetChar i of Just ('#',i@(end,_)) -> do setInput i - return (T loc end (ITprimchar ch)) + return (L (mkSrcSpan loc end) (ITprimchar ch)) _other -> - return (T loc end (ITchar ch)) - else do end <- getSrcLoc - return (T loc end (ITchar ch)) + return (L (mkSrcSpan loc end) (ITchar ch)) + else do + return (L (mkSrcSpan loc end) (ITchar ch)) + +lex_char :: P Char +lex_char = do + mc <- getCharOrFail + case mc of + '\\' -> lex_escape + c | is_any c -> return c + _other -> lit_error lex_escape :: P Char lex_escape = do @@ -1113,17 +1116,15 @@ data LayoutContext data ParseResult a = POk PState a | PFailed - SrcLoc SrcLoc -- The start and end of the text span related to + SrcSpan -- The start and end of the text span related to -- the error. Might be used in environments which can -- show this span, e.g. by highlighting it. Message -- The error message -showPFailed loc1 loc2 err = hcat [ppr loc1, text ": ", err] - data PState = PState { buffer :: StringBuffer, - last_loc :: SrcLoc, -- pos of previous token - last_len :: !Int, -- len of previous token + last_loc :: SrcSpan, -- pos of previous token + last_len :: !Int, -- len of previous token loc :: SrcLoc, -- current loc (end of prev token + 1) extsBitmap :: !Int, -- bitmap that determines permitted extensions context :: [LayoutContext], @@ -1145,17 +1146,20 @@ returnP a = P $ \s -> POk s a thenP :: P a -> (a -> P b) -> P b (P m) `thenP` k = P $ \ s -> case m s of - POk s1 a -> (unP (k a)) s1 - PFailed l1 l2 err -> PFailed l1 l2 err + POk s1 a -> (unP (k a)) s1 + PFailed span err -> PFailed span err failP :: String -> P a -failP msg = P $ \s -> PFailed (last_loc s) (loc s) (text msg) +failP msg = P $ \s -> PFailed (last_loc s) (text msg) failMsgP :: String -> P a -failMsgP msg = P $ \s -> PFailed (last_loc s) (loc s) (text msg) +failMsgP msg = P $ \s -> PFailed (last_loc s) (text msg) failLocMsgP :: SrcLoc -> SrcLoc -> String -> P a -failLocMsgP loc1 loc2 str = P $ \s -> PFailed loc1 loc2 (text str) +failLocMsgP loc1 loc2 str = P $ \s -> PFailed (mkSrcSpan loc1 loc2) (text str) + +failSpanMsgP :: SrcSpan -> String -> P a +failSpanMsgP span msg = P $ \s -> PFailed span (text msg) extension :: (Int -> Bool) -> P Bool extension p = P $ \s -> POk s (p $! extsBitmap s) @@ -1166,18 +1170,10 @@ getExts = P $ \s -> POk s (extsBitmap s) setSrcLoc :: SrcLoc -> P () setSrcLoc new_loc = P $ \s -> POk s{loc=new_loc} () --- tmp, for supporting stuff in RdrHsSyn. The scope better not include --- any calls to the lexer, because it assumes things about the SrcLoc. -setSrcLocFor :: SrcLoc -> P a -> P a -setSrcLocFor new_loc scope = P $ \s@PState{ loc = old_loc } -> - case unP scope s{loc=new_loc} of - PFailed l1 l2 msg -> PFailed l1 l2 msg - POk _ r -> POk s r - getSrcLoc :: P SrcLoc getSrcLoc = P $ \s@(PState{ loc=loc }) -> POk s loc -setLastToken :: SrcLoc -> Int -> P () +setLastToken :: SrcSpan -> Int -> P () setLastToken loc len = P $ \s -> POk s{ last_loc=loc, last_len=len } () type AlexInput = (SrcLoc,StringBuffer) @@ -1234,7 +1230,7 @@ mkPState :: StringBuffer -> SrcLoc -> DynFlags -> PState mkPState buf loc flags = PState { buffer = buf, - last_loc = loc, + last_loc = mkSrcSpan loc loc, last_len = 0, loc = loc, extsBitmap = fromIntegral bitmap, @@ -1265,14 +1261,14 @@ popContext = P $ \ s@(PState{ buffer = buf, context = ctx, loc = loc, last_len = len, last_loc = last_loc }) -> case ctx of (_:tl) -> POk s{ context = tl } () - [] -> PFailed last_loc loc (srcParseErr buf len) + [] -> PFailed last_loc (srcParseErr buf len) -- Push a new layout context at the indentation of the last token read. -- This is only used at the outer level of a module when the 'module' -- keyword is missing. pushCurrentContext :: P () pushCurrentContext = P $ \ s@PState{ last_loc=loc, context=ctx } -> - POk s{ context = Layout (srcLocCol loc) : ctx} () + POk s{ context = Layout (srcSpanStartCol loc) : ctx} () getOffside :: SrcLoc -> P Ordering getOffside loc = P $ \s@PState{context=stk} -> @@ -1302,7 +1298,7 @@ srcParseErr buf len srcParseFail :: P a srcParseFail = P $ \PState{ buffer = buf, last_len = len, last_loc = last_loc, loc = loc } -> - PFailed last_loc loc (srcParseErr buf len) + PFailed last_loc (srcParseErr buf len) -- A lexical error is reported at a particular position in the source file, -- not over a token range. TODO: this is slightly wrong, because we record @@ -1311,32 +1307,35 @@ srcParseFail = P $ \PState{ buffer = buf, last_len = len, lexError :: String -> P a lexError str = do loc <- getSrcLoc - failLocMsgP loc loc str + i@(end,_) <- getInput + failLocMsgP loc end str -- ----------------------------------------------------------------------------- -- This is the top-level function: called from the parser each time a -- new token is to be read from the input. -lexer :: (Token -> P a) -> P a +lexer :: (Located Token -> P a) -> P a lexer cont = do - tok@(T _ _ tok__) <- lexToken + tok@(L _ tok__) <- lexToken --trace ("token: " ++ show tok__) $ do cont tok -lexToken :: P Token +lexToken :: P (Located Token) lexToken = do inp@(loc1,buf) <- getInput sc <- getLexState exts <- getExts case alexScanUser exts inp sc of - AlexEOF -> do setLastToken loc1 0 - return (T loc1 loc1 ITeof) + AlexEOF -> do let span = mkSrcSpan loc1 loc1 + setLastToken span 0 + return (L span ITeof) AlexError (loc2,_) -> do failLocMsgP loc1 loc2 "lexical error" AlexSkip inp2 _ -> do setInput inp2 lexToken AlexToken inp2@(end,buf2) len t -> do setInput inp2 - setLastToken loc1 len - t loc1 end buf len + let span = mkSrcSpan loc1 end + span `seq` setLastToken span len + t span buf len }