From ff374b57fde43d3ef4e2449be631c7a8bafc68fe Mon Sep 17 00:00:00 2001 From: simonmar Date: Wed, 12 Nov 2003 14:54:32 +0000 Subject: [PATCH] [project @ 2003-11-12 14:54:32 by simonmar] oops, committed wrong version of this file --- ghc/compiler/parser/Lexer.x | 225 +++++++++++++++++++++---------------------- 1 file changed, 110 insertions(+), 115 deletions(-) diff --git a/ghc/compiler/parser/Lexer.x b/ghc/compiler/parser/Lexer.x index cd578b3..ce7c02b 100644 --- a/ghc/compiler/parser/Lexer.x +++ b/ghc/compiler/parser/Lexer.x @@ -30,6 +30,7 @@ module Lexer ( #include "HsVersions.h" +import ForeignCall ( Safety(..) ) import ErrUtils ( Message ) import Outputable import StringBuffer @@ -44,7 +45,7 @@ import Util ( maybePrefixMatch ) import DATA_BITS import Char import Ratio ---import TRACE +import TRACE } $whitechar = [\ \t\n\r\f\v\xa0] @@ -297,7 +298,7 @@ unsafeAt arr i = arr ! i -- ----------------------------------------------------------------------------- -- The token type -data Token = T SrcSpan Token__ +data Token = T SrcLoc{-start-} SrcLoc{-end-} Token__ data Token__ = ITas -- Haskell keywords @@ -541,39 +542,39 @@ reservedSymsFM = listToUFM $ -- ----------------------------------------------------------------------------- -- Lexer actions -type Action = SrcSpan -> StringBuffer -> Int -> P Token +type Action = SrcLoc -> SrcLoc -> StringBuffer -> Int -> P Token special :: Token__ -> Action -special tok span _buf len = return (T span tok) +special tok loc end _buf len = return (T loc end tok) token, layout_token :: Token__ -> Action -token t span buf len = return (T span t) -layout_token t span buf len = pushLexState layout >> return (T span t) +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) idtoken :: (StringBuffer -> Int -> Token__) -> Action -idtoken f span buf len = return (T span $! (f buf len)) +idtoken f loc end buf len = return (T loc end $! (f buf len)) skip_one_varid :: (FastString -> Token__) -> Action -skip_one_varid f span buf len - = return (T span $! f (lexemeToFastString (stepOn buf) (len-1))) +skip_one_varid f loc end buf len + = return (T loc end $! f (lexemeToFastString (stepOn buf) (len-1))) strtoken :: (String -> Token__) -> Action -strtoken f span buf len = - return (T span $! (f $! lexemeToString buf len)) +strtoken f loc end buf len = + return (T loc end $! (f $! lexemeToString buf len)) init_strtoken :: Int -> (String -> Token__) -> Action -- like strtoken, but drops the last N character(s) -init_strtoken drop f span buf len = - return (T span $! (f $! lexemeToString buf (len-drop))) +init_strtoken drop f loc end buf len = + return (T loc end $! (f $! lexemeToString buf (len-drop))) begin :: Int -> Action -begin code _span _str _len = do pushLexState code; lexToken +begin code _loc _end _str _len = do pushLexState code; lexToken pop :: Action -pop _span _buf _len = do popLexState; lexToken +pop _loc _end _buf _len = do popLexState; lexToken pop_and :: Action -> Action -pop_and act span buf len = do popLexState; act span buf len +pop_and act loc end buf len = do popLexState; act loc end buf len notFollowedBy char _ _ _ (_,buf) = atEnd buf || currentChar buf /= char @@ -587,7 +588,7 @@ ifExtension pred bits _ _ _ = pred bits using regular expressions. -} nested_comment :: Action -nested_comment span _str _len = do +nested_comment loc _end _str _len = do input <- getInput go 1 input where go 0 input = do setInput input; lexToken @@ -608,21 +609,21 @@ nested_comment span _str _len = do Just (c,input) -> go n input c -> go n input - err input = do failLocMsgP (srcSpanStart span) (fst input) "unterminated `{-'" + err input = do failLocMsgP loc (fst input) "unterminated `{-'" open_brace, close_brace :: Action -open_brace span _str _len = do +open_brace loc end _str _len = do ctx <- getContext setContext (NoLayout:ctx) - return (T span ITocurly) -close_brace span _str _len = do + return (T loc end ITocurly) +close_brace loc end _str _len = do popContext - return (T span ITccurly) + return (T loc end 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 span buf len = do +check_qvarid loc end buf len = do case lookupUFM reservedWordsFM var of Just (keyword,exts) | not (isSpecial keyword) -> @@ -635,10 +636,10 @@ check_qvarid span buf len = do _other -> return token where (mod,var) = splitQualName buf len - token = T span (ITqvarid (mod,var)) + token = T loc end (ITqvarid (mod,var)) try_again = do - setInput (srcSpanStart span,buf) + setInput (loc,buf) pushLexState bad_qvarid lexToken @@ -667,17 +668,17 @@ 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 span buf len = +varid loc end buf len = case lookupUFM reservedWordsFM fs of Just (keyword,0) -> do maybe_layout keyword - return (T span keyword) + return (T loc end keyword) Just (keyword,exts) -> do b <- extension (\i -> exts .&. i /= 0) if b then do maybe_layout keyword - return (T span keyword) - else return (T span (ITvarid fs)) - _other -> return (T span (ITvarid fs)) + return (T loc end keyword) + else return (T loc end (ITvarid fs)) + _other -> return (T loc end (ITvarid fs)) where fs = lexemeToFastString buf len @@ -690,34 +691,34 @@ qconsym buf len = ITqconsym $! splitQualName buf len varsym = sym ITvarsym consym = sym ITconsym -sym con span buf len = +sym con loc end buf len = case lookupUFM reservedSymsFM fs of - Just (keyword,0) -> return (T span keyword) + Just (keyword,0) -> return (T loc end keyword) Just (keyword,exts) -> do b <- extension (\i -> exts .&. i /= 0) - if b then return (T span keyword) - else return (T span $! con fs) - _other -> return (T span $! con fs) + if b then return (T loc end keyword) + else return (T loc end $! con fs) + _other -> return (T loc end $! con fs) where fs = lexemeToFastString buf len -tok_decimal span buf len - = return (T span (ITinteger $! parseInteger buf len 10 oct_or_dec)) +tok_decimal loc end buf len + = return (T loc end (ITinteger $! parseInteger buf len 10 oct_or_dec)) -tok_octal span buf len - = return (T span (ITinteger $! parseInteger (stepOnBy 2 buf) (len-2) 8 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_hexadecimal span buf len - = return (T span (ITinteger $! parseInteger (stepOnBy 2 buf) (len-2) 16 hex)) +tok_hexadecimal loc end buf len + = return (T loc end (ITinteger $! parseInteger (stepOnBy 2 buf) (len-2) 16 hex)) -prim_decimal span buf len - = return (T span (ITprimint $! parseInteger buf (len-1) 10 oct_or_dec)) +prim_decimal loc end buf len + = return (T loc end (ITprimint $! parseInteger buf (len-1) 10 oct_or_dec)) -prim_octal span buf len - = return (T span (ITprimint $! parseInteger (stepOnBy 2 buf) (len-3) 8 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_hexadecimal span buf len - = return (T span (ITprimint $! parseInteger (stepOnBy 2 buf) (len-3) 16 hex)) +prim_hexadecimal loc end buf len + = return (T loc end (ITprimint $! parseInteger (stepOnBy 2 buf) (len-3) 16 hex)) tok_float str = ITrational $! readRational__ str prim_float str = ITprimfloat $! readRational__ str @@ -734,18 +735,18 @@ 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 span _str _len = do - pos <- getOffside (srcSpanEndCol span) +do_bol loc end _str _len = do + pos <- getOffside end case pos of LT -> do --trace "layout: inserting '}'" $ do popContext -- do NOT pop the lex state, we might have a ';' to insert - return (T span ITvccurly) + return (T loc end ITvccurly) EQ -> do --trace "layout: inserting ';'" $ do popLexState - return (T span ITsemi) + return (T loc end ITsemi) GT -> do popLexState lexToken @@ -769,9 +770,9 @@ 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 span _buf _len = do +new_layout_context strict loc end _buf _len = do popLexState - let offset = srcSpanStartCol span + let offset = srcLocCol loc ctx <- getContext case ctx of Layout prev_off : _ | @@ -780,32 +781,32 @@ new_layout_context strict span _buf _len = do -- token is indented to the left of the previous context. -- we must generate a {} sequence now. pushLexState layout_left - return (T span ITvocurly) + return (T loc end ITvocurly) other -> do setContext (Layout offset : ctx) - return (T span ITvocurly) + return (T loc end ITvocurly) -do_layout_left span _buf _len = do +do_layout_left loc end _buf _len = do popLexState pushLexState bol -- we must be at the start of a line - return (T span ITvccurly) + return (T loc end ITvccurly) -- ----------------------------------------------------------------------------- -- LINE pragmas set_line :: Int -> Action -set_line code span buf len = do +set_line code loc end buf len = do let line = parseInteger buf len 10 oct_or_dec - setSrcLoc (mkSrcLoc (srcSpanFile span) (fromIntegral line - 1) 0) + setSrcLoc (mkSrcLoc (srcLocFile end) (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 span buf len = do +set_file code loc end buf len = do let file = lexemeToFastString (stepOn buf) (len-2) - setSrcLoc (mkSrcLoc file (srcSpanEndLine span) (srcSpanEndCol span)) + setSrcLoc (mkSrcLoc file (srcLocLine end) (srcLocCol end)) popLexState pushLexState code lexToken @@ -816,10 +817,10 @@ set_file code span buf len = do -- This stuff is horrible. I hates it. lex_string_tok :: Action -lex_string_tok span buf len = do +lex_string_tok loc end buf len = do tok <- lex_string "" end <- getSrcLoc - return (T (mkSrcSpan (srcSpanStart span) end) tok) + return (T loc end tok) lex_string :: String -> P Token__ lex_string s = do @@ -857,6 +858,14 @@ 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 @@ -872,9 +881,8 @@ 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 span buf len = do -- We've seen ' +lex_char_tok loc _end buf len = do -- We've seen ' i1 <- getInput -- Look ahead to first character - let loc = srcSpanStart span case alexGetChar i1 of Nothing -> lit_error @@ -882,7 +890,7 @@ lex_char_tok span buf len = do -- We've seen ' th_exts <- extension thEnabled if th_exts then do setInput i2 - return (T (mkSrcSpan loc end2) ITtyQuote) + return (T loc end2 ITtyQuote) else lit_error Just ('\\', i2@(end2,_)) -> do -- We've seen 'backslash @@ -905,7 +913,7 @@ lex_char_tok span 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 (mkSrcSpan loc (fst i1)) ITvarQuote) + if th_exts then return (T loc (fst i1) ITvarQuote) else lit_error finish_char_tok :: SrcLoc -> Char -> P Token @@ -917,20 +925,11 @@ finish_char_tok loc ch -- We've already seen the closing quote case alexGetChar i of Just ('#',i@(end,_)) -> do setInput i - return (T (mkSrcSpan loc end) (ITprimchar ch)) + return (T loc end (ITprimchar ch)) _other -> - return (T (mkSrcSpan loc end) (ITchar ch)) - else do - end <- getSrcLoc - return (T (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 + return (T loc end (ITchar ch)) + else do end <- getSrcLoc + return (T loc end (ITchar ch)) lex_escape :: P Char lex_escape = do @@ -1114,26 +1113,24 @@ data LayoutContext data ParseResult a = POk PState a | PFailed - SrcSpan -- The spam the error. Might be used in environments - -- which can show this span, e.g. by highlighting it. + SrcLoc SrcLoc -- 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 span err = hcat [ppr span, text ": ", err] +showPFailed loc1 loc2 err = hcat [ppr loc1, text ": ", err] data PState = PState { buffer :: StringBuffer, - last_span :: SrcSpan, -- span of previous token - last_len :: !Int, + last_loc :: SrcLoc, -- 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], lex_state :: [Int] } - -- last_span is used when generating error messages, + -- last_loc and last_len are used when generating error messages, -- and in pushCurrentContext only. - -- last_len is used when generating error messages, and is - -- needed because we need to back up the buffer pointer by that - -- number of characters for outputing the token in the error message. newtype P a = P { unP :: PState -> ParseResult a } @@ -1148,17 +1145,17 @@ 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 span err -> PFailed span err + POk s1 a -> (unP (k a)) s1 + PFailed l1 l2 err -> PFailed l1 l2 err failP :: String -> P a -failP msg = P $ \s -> PFailed (last_span s) (text msg) +failP msg = P $ \s -> PFailed (last_loc s) (loc s) (text msg) failMsgP :: String -> P a -failMsgP msg = P $ \s -> PFailed (last_span s) (text msg) +failMsgP msg = P $ \s -> PFailed (last_loc s) (loc s) (text msg) failLocMsgP :: SrcLoc -> SrcLoc -> String -> P a -failLocMsgP loc1 loc2 str = P $ \s -> PFailed (mkSrcSpan loc1 loc2) (text str) +failLocMsgP loc1 loc2 str = P $ \s -> PFailed loc1 loc2 (text str) extension :: (Int -> Bool) -> P Bool extension p = P $ \s -> POk s (p $! extsBitmap s) @@ -1174,14 +1171,14 @@ setSrcLoc new_loc = P $ \s -> POk s{loc=new_loc} () 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 span msg -> PFailed span msg + 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 :: SrcSpan -> Int -> P () -setLastToken span len = P $ \s -> POk s{ last_span=span, last_len=len } () +setLastToken :: SrcLoc -> Int -> P () +setLastToken loc len = P $ \s -> POk s{ last_loc=loc, last_len=len } () type AlexInput = (SrcLoc,StringBuffer) @@ -1237,7 +1234,7 @@ mkPState :: StringBuffer -> SrcLoc -> DynFlags -> PState mkPState buf loc flags = PState { buffer = buf, - last_span = mkSrcSpan loc loc, + last_loc = loc, last_len = 0, loc = loc, extsBitmap = fromIntegral bitmap, @@ -1265,24 +1262,24 @@ setContext ctx = P $ \s -> POk s{context=ctx} () popContext :: P () popContext = P $ \ s@(PState{ buffer = buf, context = ctx, - loc = loc, last_len = len, last_span = last_span }) -> + loc = loc, last_len = len, last_loc = last_loc }) -> case ctx of (_:tl) -> POk s{ context = tl } () - [] -> PFailed last_span (srcParseErr buf len) + [] -> PFailed last_loc 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_span=span, context=ctx } -> - POk s{ context = Layout (srcSpanStartCol span) : ctx} () +pushCurrentContext = P $ \ s@PState{ last_loc=loc, context=ctx } -> + POk s{ context = Layout (srcLocCol loc) : ctx} () -getOffside :: Int -> P Ordering -getOffside col = P $ \s@PState{context=stk} -> +getOffside :: SrcLoc -> P Ordering +getOffside loc = P $ \s@PState{context=stk} -> let ord = case stk of - (Layout n:_) -> compare col n + (Layout n:_) -> compare (srcLocCol loc) n _ -> GT - in POk s $! ord + in POk s ord -- --------------------------------------------------------------------------- -- Construct a parse error @@ -1304,8 +1301,8 @@ srcParseErr buf len -- detected during parsing. srcParseFail :: P a srcParseFail = P $ \PState{ buffer = buf, last_len = len, - last_span = last_span, loc = loc } -> - PFailed last_span (srcParseErr buf len) + last_loc = last_loc, loc = loc } -> + PFailed last_loc 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 @@ -1322,7 +1319,7 @@ lexError str = do lexer :: (Token -> P a) -> P a lexer cont = do - tok@(T _ tok__) <- lexToken + tok@(T _ _ tok__) <- lexToken --trace ("token: " ++ show tok__) $ do cont tok @@ -1332,16 +1329,14 @@ lexToken = do sc <- getLexState exts <- getExts case alexScanUser exts inp sc of - AlexEOF -> do let span = mkSrcSpan loc1 loc1 - setLastToken span 0 - return (T span ITeof) + AlexEOF -> do setLastToken loc1 0 + return (T loc1 loc1 ITeof) AlexError (loc2,_) -> do failLocMsgP loc1 loc2 "lexical error" AlexSkip inp2 _ -> do setInput inp2 lexToken AlexToken inp2@(end,buf2) len t -> do setInput inp2 - let span = mkSrcSpan loc1 end - (setLastToken $! span) $! len - t span buf len + setLastToken loc1 len + t loc1 end buf len } -- 1.7.10.4