X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fparser%2FLexer.x;h=db48dbe7c6967fdaf42c54c45d0bc91cf881500b;hb=2eb04ca0f8d0ec72b417cddc60672c696b4a3daa;hp=d9a0fb08b0e28e578d7a115ce0995fb14f90ce7b;hpb=317fc69d18eda68fd65f5ba634feafbe4a3923da;p=ghc-hetmet.git diff --git a/compiler/parser/Lexer.x b/compiler/parser/Lexer.x index d9a0fb0..db48dbe 100644 --- a/compiler/parser/Lexer.x +++ b/compiler/parser/Lexer.x @@ -58,30 +58,30 @@ import Compat.Unicode ( GeneralCategory(..), generalCategory, isPrint, isUpper ) #endif } -$unispace = \x05 +$unispace = \x05 -- Trick Alex into handling Unicode. See alexGetChar. $whitechar = [\ \n\r\f\v\xa0 $unispace] $white_no_nl = $whitechar # \n $tab = \t $ascdigit = 0-9 -$unidigit = \x03 +$unidigit = \x03 -- Trick Alex into handling Unicode. See alexGetChar. $decdigit = $ascdigit -- for now, should really be $digit (ToDo) $digit = [$ascdigit $unidigit] $special = [\(\)\,\;\[\]\`\{\}] $ascsymbol = [\!\#\$\%\&\*\+\.\/\<\=\>\?\@\\\^\|\-\~ \xa1-\xbf \xd7 \xf7] -$unisymbol = \x04 +$unisymbol = \x04 -- Trick Alex into handling Unicode. See alexGetChar. $symbol = [$ascsymbol $unisymbol] # [$special \_\:\"\'] -$unilarge = \x01 +$unilarge = \x01 -- Trick Alex into handling Unicode. See alexGetChar. $asclarge = [A-Z \xc0-\xd6 \xd8-\xde] $large = [$asclarge $unilarge] -$unismall = \x02 +$unismall = \x02 -- Trick Alex into handling Unicode. See alexGetChar. $ascsmall = [a-z \xdf-\xf6 \xf8-\xff] $small = [$ascsmall $unismall \_] -$unigraphic = \x06 +$unigraphic = \x06 -- Trick Alex into handling Unicode. See alexGetChar. $graphic = [$small $large $symbol $digit $special $unigraphic \:\"\'] $octit = 0-7 @@ -108,6 +108,11 @@ $docsym = [\| \^ \* \$] @floating_point = @decimal \. @decimal @exponent? | @decimal @exponent +-- normal signed numerical literals can only be explicitly negative, +-- not explicitly positive (contrast @exponent) +@negative = \- +@signed = @negative ? + haskell :- -- everywhere: skip whitespace and comments @@ -271,8 +276,8 @@ $tab+ { warn Opt_WarnTabs (text "Tab character") } -- Haddock comments <0,glaexts> { - "-- " / $docsym { multiline_doc_comment } - "{-" \ ? / $docsym { nested_doc_comment } + "-- " $docsym / { ifExtension haddockEnabled } { multiline_doc_comment } + "{-" \ ? $docsym / { ifExtension haddockEnabled } { nested_doc_comment } } -- "special" symbols @@ -353,22 +358,35 @@ $tab+ { warn Opt_WarnTabs (text "Tab character") } @consym { consym } } +-- For the normal boxed literals we need to be careful +-- when trying to be close to Haskell98 <0,glaexts> { - @decimal { tok_decimal } - 0[oO] @octal { tok_octal } - 0[xX] @hexadecimal { tok_hexadecimal } + -- Normal integral literals (:: Num a => a, from Integer) + @decimal { tok_num positive 0 0 decimal } + 0[oO] @octal { tok_num positive 2 2 octal } + 0[xX] @hexadecimal { tok_num positive 2 2 hexadecimal } + + -- Normal rational literals (:: Fractional a => a, from Rational) + @floating_point { strtoken tok_float } } { - @decimal \# { prim_decimal } - 0[oO] @octal \# { prim_octal } - 0[xX] @hexadecimal \# { prim_hexadecimal } + -- Unboxed ints (:: Int#) + -- It's simpler (and faster?) to give separate cases to the negatives, + -- especially considering octal/hexadecimal prefixes. + @decimal \# { tok_primint positive 0 1 decimal } + 0[oO] @octal \# { tok_primint positive 2 3 octal } + 0[xX] @hexadecimal \# { tok_primint positive 2 3 hexadecimal } + @negative @decimal \# { tok_primint negative 1 2 decimal } + @negative 0[oO] @octal \# { tok_primint negative 3 4 octal } + @negative 0[xX] @hexadecimal \# { tok_primint negative 3 4 hexadecimal } + + -- Unboxed floats and doubles (:: Float#, :: Double#) + -- prim_{float,double} work with signed literals + @signed @floating_point \# { init_strtoken 1 tok_primfloat } + @signed @floating_point \# \# { init_strtoken 2 tok_primdouble } } -<0,glaexts> @floating_point { strtoken tok_float } - @floating_point \# { init_strtoken 1 prim_float } - @floating_point \# \# { init_strtoken 2 prim_double } - -- Strings and chars are lexed by hand-written code. The reason is -- that even if we recognise the string or char here in the regex -- lexer, we would still have to parse the string afterward in order @@ -597,7 +615,7 @@ reservedWordsFM = listToUFM $ ( "forall", ITforall, bit tvBit), ( "mdo", ITmdo, bit glaExtsBit), - ( "family", ITfamily, bit idxTysBit), + ( "family", ITfamily, bit tyFamBit), ( "foreign", ITforeign, bit ffiBit), ( "export", ITexport, bit ffiBit), @@ -632,7 +650,7 @@ reservedSymsFM = listToUFM $ ,("!", ITbang, 0) ,("*", ITstar, bit glaExtsBit .|. - bit idxTysBit) -- For data T (a::*) = MkT + bit tyFamBit) -- For data T (a::*) = MkT ,(".", ITdot, bit tvBit) -- For 'forall a . t' ,("-<", ITlarrowtail, bit arrowsBit) @@ -646,7 +664,7 @@ reservedSymsFM = listToUFM $ ,("∀", ITforall, bit glaExtsBit) ,("→", ITrarrow, bit glaExtsBit) ,("←", ITlarrow, bit glaExtsBit) - ,("?", ITdotdot, bit glaExtsBit) + ,("⋯", ITdotdot, bit glaExtsBit) -- ToDo: ideally, → and ∷ should be "specials", so that they cannot -- form part of a large operator. This would let us have a better -- syntax for kinds: ɑ∷*→* would be a legal kind signature. (maybe). @@ -699,12 +717,17 @@ notFollowedBy char _ _ _ (AI _ _ buf) notFollowedBySymbol _ _ _ (AI _ _ buf) = nextCharIs buf (`notElem` "!#$%&*+./<=>?@\\^|-~") +-- We must reject doc comments as being ordinary comments everywhere. +-- In some cases the doc comment will be selected as the lexeme due to +-- maximal munch, but not always, because the nested comment rule is +-- valid in all states, but the doc-comment rules are only valid in +-- the non-layout states. isNormalComment bits _ _ (AI _ _ buf) | haddockEnabled bits = notFollowedByDocOrPragma | otherwise = nextCharIs buf (/='#') - where - notFollowedByDocOrPragma - = not $ spaceAndP buf (`nextCharIs` (`elem` "|^*$#")) + where + notFollowedByDocOrPragma + = not $ spaceAndP buf (`nextCharIs` (`elem` "|^*$#")) spaceAndP buf p = p buf || nextCharIs buf (==' ') && p (snd (nextChar buf)) @@ -785,13 +808,12 @@ nested_doc_comment span buf _len = withLexedDocType (go "") Just (c,input) -> go (c:commentAcc) input docType False withLexedDocType lexDocComment = do - input <- getInput - case alexGetChar input of - Nothing -> error "Can't happen" - Just ('|', input) -> lexDocComment input ITdocCommentNext False - Just ('^', input) -> lexDocComment input ITdocCommentPrev False - Just ('$', input) -> lexDocComment input ITdocCommentNamed False - Just ('*', input) -> lexDocSection 1 input + input@(AI _ _ buf) <- getInput + case prevChar buf ' ' of + '|' -> lexDocComment input ITdocCommentNext False + '^' -> lexDocComment input ITdocCommentPrev False + '$' -> lexDocComment input ITdocCommentNamed False + '*' -> lexDocSection 1 input where lexDocSection n input = case alexGetChar input of Just ('*', input) -> lexDocSection (n+1) input @@ -930,27 +952,29 @@ sym con span buf len = where fs = lexemeToFastString buf len -tok_decimal span buf len - = return (L span (ITinteger $! parseInteger buf len 10 octDecDigit)) - -tok_octal span buf len - = return (L span (ITinteger $! parseInteger (offsetBytes 2 buf) (len-2) 8 octDecDigit)) - -tok_hexadecimal span buf len - = return (L span (ITinteger $! parseInteger (offsetBytes 2 buf) (len-2) 16 hexDigit)) - -prim_decimal span buf len - = return (L span (ITprimint $! parseInteger buf (len-1) 10 octDecDigit)) - -prim_octal span buf len - = return (L span (ITprimint $! parseInteger (offsetBytes 2 buf) (len-3) 8 octDecDigit)) - -prim_hexadecimal span buf len - = return (L span (ITprimint $! parseInteger (offsetBytes 2 buf) (len-3) 16 hexDigit)) - +-- Variations on the integral numeric literal. +tok_integral :: (Integer -> Token) + -> (Integer -> Integer) + -- -> (StringBuffer -> StringBuffer) -> (Int -> Int) + -> Int -> Int + -> (Integer, (Char->Int)) -> Action +tok_integral itint transint transbuf translen (radix,char_to_int) span buf len = + return $ L span $ itint $! transint $ parseUnsignedInteger + (offsetBytes transbuf buf) (subtract translen len) radix char_to_int + +-- some conveniences for use with tok_integral +tok_num = tok_integral ITinteger +tok_primint = tok_integral ITprimint +positive = id +negative = negate +decimal = (10,octDecDigit) +octal = (8,octDecDigit) +hexadecimal = (16,hexDigit) + +-- readRational can understand negative rationals, exponents, everything. tok_float str = ITrational $! readRational str -prim_float str = ITprimfloat $! readRational str -prim_double str = ITprimdouble $! readRational str +tok_primfloat str = ITprimfloat $! readRational str +tok_primdouble str = ITprimdouble $! readRational str -- ----------------------------------------------------------------------------- -- Layout processing @@ -1018,7 +1042,7 @@ do_layout_left span _buf _len = do setLine :: Int -> Action setLine code span buf len = do - let line = parseInteger buf len 10 octDecDigit + let line = parseUnsignedInteger buf len 10 octDecDigit setSrcLoc (mkSrcLoc (srcSpanFile span) (fromIntegral line - 1) 0) -- subtract one: the line number refers to the *following* line popLexState @@ -1415,6 +1439,9 @@ alexGetChar (AI loc ofs s) adj_c | c <= '\x06' = non_graphic | c <= '\xff' = c + -- Alex doesn't handle Unicode, so when Unicode + -- character is encoutered we output these values + -- with the actual character value hidden in the state. | otherwise = case generalCategory c of UppercaseLetter -> upper @@ -1488,7 +1515,7 @@ ipBit = 6 tvBit = 7 -- Scoped type variables enables 'forall' keyword bangPatBit = 8 -- Tells the parser to understand bang-patterns -- (doesn't affect the lexer) -idxTysBit = 9 -- indexed type families: 'family' keyword and kind sigs +tyFamBit = 9 -- indexed type families: 'family' keyword and kind sigs haddockBit = 10 -- Lex and parse Haddock comments glaExtsEnabled, ffiEnabled, parrEnabled :: Int -> Bool @@ -1500,7 +1527,7 @@ thEnabled flags = testBit flags thBit ipEnabled flags = testBit flags ipBit tvEnabled flags = testBit flags tvBit bangPatEnabled flags = testBit flags bangPatBit -idxTysEnabled flags = testBit flags idxTysBit +tyFamEnabled flags = testBit flags tyFamBit haddockEnabled flags = testBit flags haddockBit -- PState for parsing options pragmas @@ -1543,16 +1570,16 @@ mkPState buf loc flags = -- we begin in the layout state if toplev_layout is set } where - bitmap = glaExtsBit `setBitIf` dopt Opt_GlasgowExts flags - .|. ffiBit `setBitIf` dopt Opt_FFI flags - .|. parrBit `setBitIf` dopt Opt_PArr flags - .|. arrowsBit `setBitIf` dopt Opt_Arrows flags - .|. thBit `setBitIf` dopt Opt_TH flags + bitmap = glaExtsBit `setBitIf` dopt Opt_GlasgowExts flags + .|. ffiBit `setBitIf` dopt Opt_FFI flags + .|. parrBit `setBitIf` dopt Opt_PArr flags + .|. arrowsBit `setBitIf` dopt Opt_Arrows flags + .|. thBit `setBitIf` dopt Opt_TH flags .|. ipBit `setBitIf` dopt Opt_ImplicitParams flags .|. tvBit `setBitIf` dopt Opt_ScopedTypeVariables flags .|. bangPatBit `setBitIf` dopt Opt_BangPatterns flags - .|. idxTysBit `setBitIf` dopt Opt_IndexedTypes flags - .|. haddockBit `setBitIf` dopt Opt_Haddock flags + .|. tyFamBit `setBitIf` dopt Opt_TypeFamilies flags + .|. haddockBit `setBitIf` dopt Opt_Haddock flags -- setBitIf :: Int -> Bool -> Int b `setBitIf` cond | cond = bit b