X-Git-Url: https://git.martlubbers.net/?a=blobdiff_plain;f=lex.icl;h=aa34987969b5afcdc71c83451f91fe448ee9902f;hb=d0e8cca079e8b36453b3eeee66b25681e5423f18;hp=876e3020563af235fb2604aac839e35132111f55;hpb=1ee1a90bd336cd6c44ab4b51dd7f4946447ce8a8;p=cc1516.git diff --git a/lex.icl b/lex.icl index 876e302..aa34987 100644 --- a/lex.icl +++ b/lex.icl @@ -1,69 +1,118 @@ implementation module lex -import Control.Monad -import Data.Either -import Data.Maybe -import Data.Map -import Data.Func -import StdString -import StdTuple +import Control.Monad, Control.Applicative +import Data.Either, Data.Func, Data.Void +from StdFunc import o import StdBool import StdList import StdChar -import qualified Text +import StdString +import StdTuple -SingleCharTokens :: Map Char Token -SingleCharTokens = fromList [ - ('(', BraceOpenToken), (')', BraceCloseToken), ('{', CBraceOpenToken), - ('}', CBraceCloseToken), ('[', SquareOpenToken), (']', SquareCloseToken), - (',', CommaToken), (':', ColonToken), (';', SColonToken), - ('.', DotToken), ('+', PlusToken), ('-', DashToken), ('*', StarToken), - ('/', SlashToken), ('%', PercentToken), ('=', AssignmentToken), - ('<', LesserToken), ('>', BiggerToken), ('!', ExclamationToken)] +import yard +import AST -EscapeMap :: Map Char Char -EscapeMap = fromList [('a', toChar 7), ('b', '\b'), ('f', '\f'), ('n', '\n'), - ('r', '\r'), ('t', '\t'), ('v', '\v')] +:: LexItem + = LexToken Int TokenValue + | LexSpace Int Int + | LexNL + | LexEOF + | LexItemError String lexer :: [Char] -> LexerOutput -lexer [] = Right [] -lexer x = case lex x of - (Right t, rest) = lexer rest >>= \ts.Right [t:ts] - (Left e, _) = Left e +lexer r = fst $ runParser (lexProgram 1 1) r + +lexProgram :: Int Int -> Parser Char [Token] +lexProgram line column = lexToken >>= \t->case t of + LexEOF = pure [] + LexNL = lexProgram (line+1) 1 + (LexSpace l c) = lexProgram (line+l) (column+c) + (LexItemError e) = fail + PositionalError line column ("LexerError: " +++ e) + (LexToken c t) = lexProgram line (column+c) + >>= \rest->pure [({line=line,col=column}, t):rest] + +lexToken :: Parser Char LexItem +lexToken = + //Comments + lexBlockComment <|> lexComment <|> + //Keyword tokens + lexKw "var" VarToken <|> lexKw "Void" VoidToken <|> + lexKw "return" ReturnToken <|> lexKw "if" IfToken <|> + lexKw "else" ElseToken <|> lexKw "while" WhileToken <|> + lexKw "True" TrueToken <|> lexKw "False" FalseToken <|> + lexKw "Int" IntTypeToken <|> lexKw "Bool" BoolTypeToken <|> + lexKw "Char" CharTypeToken <|> + //Character tokens + lexEscape <|> lexCharacter <|> + //Two char ops tokens + lexWord "::" DoubleColonToken <|> lexWord "!=" NotEqualToken <|> + lexWord "<=" LesserEqToken <|> lexWord ">=" GreaterEqToken <|> + lexWord "==" EqualsToken <|> lexWord "&&" AmpersandsToken <|> + lexWord "||" PipesToken <|> lexWord "[]" EmptyListToken <|> + lexWord "->" ArrowToken <|> + //One char ops tokens + lexWord "(" BraceOpenToken <|> lexWord ")" BraceCloseToken <|> + lexWord "{" CBraceOpenToken <|> lexWord "}" CBraceCloseToken <|> + lexWord "[" SquareOpenToken <|> lexWord "]" SquareCloseToken <|> + lexWord "," CommaToken <|> lexWord ":" ColonToken <|> + lexWord ";" SColonToken <|> lexWord "." DotToken <|> + lexWord "+" PlusToken <|> lexWord "*" StarToken <|> + lexWord "/" SlashToken <|> lexWord "%" PercentToken <|> + lexWord "=" AssignmentToken <|> lexWord "<" LesserToken <|> + lexWord ">" BiggerToken <|> lexWord "!" ExclamationToken <|> + lexWord "-" DashToken <|> + //Number and identifier tokens + lexNumber <|> lexIdentifier <|> + (item '\n' >>| pure LexNL) <|> + //Whitespace + (satisfy isSpace >>| (pure $ LexSpace 0 1)) <|> + (eof >>| pure LexEOF) + where + lexWord :: String TokenValue -> Parser Char LexItem + lexWord s tv = list ls >>| pure (LexToken (length ls) tv) + where ls = fromString s + + lexKw :: String TokenValue -> Parser Char LexItem + lexKw kw tv = lexWord kw tv <* check (not o isIdentChar) + + lexComment :: Parser Char LexItem + lexComment = list (fromString "//") + >>| top until (eof <|> (item '\n' >>| pure Void)) >>| pure LexNL + + lexBlockComment :: Parser Char LexItem + lexBlockComment = list (fromString "/*") + >>| (top until (list (fromString "*/"))) + >>= \chars->pure $ widthHeight chars 0 0 + where + widthHeight :: [Char] Int Int -> LexItem + widthHeight [] l c = LexSpace l c + widthHeight ['\n':xs] l _ = widthHeight xs (l+1) 0 + widthHeight [x:xs] l c = widthHeight xs l (c+1) + + lexNumber :: Parser Char LexItem + lexNumber = some (satisfy isDigit) >>= \si->pure $ + LexToken (length si) (NumberToken $ toInt $ toString si) + + lexIdentifier :: Parser Char LexItem + lexIdentifier = some (satisfy isIdentChar) + >>= \si->pure $ LexToken (length si) (IdentToken $ toString si) + + isIdentChar c = isAlphanum c || c == '_' + + lexCharacter :: Parser Char LexItem + lexCharacter = item '\'' *> satisfy ((<>) '\'') <* item '\'' + >>= \char->pure $ LexToken 3 (CharToken char) -lex :: [Char] -> (Either String Token, [Char]) -lex [] = (Right EndOfFileToken, []) -lex ['/':'/':xs] = lex $ dropWhile ((<>) '\n') xs -lex ['/':'*':xs] = lex $ tl $ map snd $ dropWhile ((<>) ('*', '/')) $ zip2 [zero:xs] xs -lex ['v':'a':'r':xs] = (Right VarToken, xs) -lex ['V':'o':'i':'d':xs] = (Right VoidToken, xs) -lex ['r':'e':'t':'u':'r':'n':xs] = (Right ReturnToken, xs) -lex ['i':'f':xs] = (Right IfToken, xs) -lex ['e':'l':'s':'e':xs] = (Right ElseToken, xs) -lex ['w':'h':'i':'l':'e':xs] = (Right WhileToken, xs) -lex ['T':'r':'u':'e':xs] = (Right TrueToken, xs) -lex ['F':'a':'l':'s':'e':xs] = (Right FalseToken, xs) -lex ['I':'n':'t':xs] = (Right IntTypeToken, xs) -lex ['C':'h':'a':'r':xs] = (Right CharTypeToken, xs) -lex ['B':'o':'o':'l':xs] = (Right BoolTypeToken, xs) -lex [':':':':xs] = (Right DoubleColonToken, xs) -lex ['!':'=':xs] = (Right NotEqualToken, xs) -lex ['<':'=':xs] = (Right LesserEqToken, xs) -lex ['>':'=':xs] = (Right GreaterEqToken, xs) -lex ['=':'=':xs] = (Right EqualsToken, xs) -lex ['&':'&':xs] = (Right AmpersandsToken, xs) -lex ['|':'|':xs] = (Right PipesToken, xs) -lex ['-':'>':xs] = (Right ArrowToken, xs) -lex ['\'':x:'\'':xs] = (Right (CharToken x), xs) -lex ['\'':'\\':x:'\'':xs] = case get x EscapeMap of - Just t = (Right (CharToken t), xs) - _ = (Left ("Unknown escape: \\" +++ toString x), []) -lex [x:xs] -# t = get x SingleCharTokens -| isJust t = (Right (fromJust t), xs) -| isSpace x = lex xs -| isDigit x = let (is, xs`) = span isDigit xs in - (Right (NumberToken [x:is]), xs`) -| isAlpha x = let (is, xs`) = span (\c.isAlphanum c || c == '_') xs in - (Right (IdentToken [x:is]), xs`) -| otherwise = (Left ("Unexpected character: " +++ toString x), []) + lexEscape :: Parser Char LexItem + lexEscape = item '\'' *> item '\\' *> top <* item '\'' + >>= \char->pure case char of + 'a' = LexToken 4 (CharToken $ toChar 7) + 'b' = LexToken 4 (CharToken '\b') + 'b' = LexToken 4 (CharToken '\b') + 'f' = LexToken 4 (CharToken '\f') + 'n' = LexToken 4 (CharToken '\n') + 'r' = LexToken 4 (CharToken '\t') + 'v' = LexToken 4 (CharToken '\v') + '\'' =LexToken 4 (CharToken '\'') + c = (LexItemError $ "Unknown escape: " +++ toString c)