X-Git-Url: https://git.martlubbers.net/?a=blobdiff_plain;f=lex.icl;h=aa34987969b5afcdc71c83451f91fe448ee9902f;hb=a8348a333a567e5a469d1e5f8ec6c3dafc051c91;hp=de200df2f4dcd62930ea1e74bf20f97fb7b9872a;hpb=75ac4a13efdc20b444a5eb6cb2d16425c82d333e;p=cc1516.git

diff --git a/lex.icl b/lex.icl
index de200df..aa34987 100644
--- a/lex.icl
+++ b/lex.icl
@@ -1,80 +1,118 @@
 implementation module lex
 
-import Control.Monad
-import Data.Either, Data.Maybe, Data.Map, 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 StdString
+import StdTuple
 
-SingleCharTokens :: Map Char TokenValue
-SingleCharTokens = fromList [
-	('(', BraceOpenToken), (')', BraceCloseToken), ('{', CBraceOpenToken),
-	('}', CBraceCloseToken), ('[', SquareOpenToken), (']', SquareCloseToken),
-	(',', CommaToken), (':', ColonToken), (';', SColonToken),
-	('.', DotToken), ('+', PlusToken), ('*', 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 x = lexer` x 1
+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
-		lexer` :: [Char] Int -> LexerOutput
-		lexer` [] i = Right []
-		lexer` x i = case lex x i of
-			(Right t, rest, i) = lexer` rest i >>= \ts.Right [t:ts]
-			(Left e, _, _) = Left e
+		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)
 
-ret:: TokenValue [Char] Int -> (Either String Token, [Char], Int)
-ret tv rest i = (Right (i, tv), rest, i)
+		isIdentChar c = isAlphanum c || c == '_'
 
-err :: String Int -> (Either String Token, [Char], Int)
-err s i = (Left ("Line " +++ toString i +++ ": " +++ s), [], i)
+		lexCharacter :: Parser Char LexItem
+		lexCharacter = item '\'' *> satisfy ((<>) '\'') <* item '\''
+			>>= \char->pure $ LexToken 3 (CharToken char)
 
-lex :: [Char] -> (Int -> (Either String Token, [Char], Int))
-lex [] = ret EndOfFileToken []
-lex ['/':'/':xs] = lex (dropWhile ((<>) '\n') xs)
-lex ['/':'*':xs] =  \i.let (c, r) = span ((<>) ('*','/')) $ zip2 [' ':xs] xs in
-	lex (tl $ map snd $ tl $ r) (i + length [x\\(x, _)<-c | x == '\n'])
-lex ['v':'a':'r':xs] = ret VarToken xs
-lex ['V':'o':'i':'d':xs] = ret VoidToken xs
-lex ['r':'e':'t':'u':'r':'n':xs] = ret ReturnToken xs
-lex ['i':'f':xs] = ret IfToken xs
-lex ['e':'l':'s':'e':xs] = ret ElseToken xs
-lex ['w':'h':'i':'l':'e':xs] = ret WhileToken xs
-lex ['T':'r':'u':'e':xs] = ret TrueToken xs
-lex ['F':'a':'l':'s':'e':xs] = ret FalseToken xs
-lex ['I':'n':'t':xs] = ret IntTypeToken xs
-lex ['C':'h':'a':'r':xs] = ret CharTypeToken xs
-lex ['B':'o':'o':'l':xs] = ret BoolTypeToken xs
-lex [':':':':xs] = ret DoubleColonToken xs
-lex ['!':'=':xs] = ret NotEqualToken xs
-lex ['<':'=':xs] = ret LesserEqToken xs
-lex ['>':'=':xs] = ret GreaterEqToken xs
-lex ['=':'=':xs] = ret EqualsToken xs
-lex ['&':'&':xs] = ret AmpersandsToken xs
-lex ['|':'|':xs] = ret PipesToken xs
-lex ['-':'>':xs] = ret ArrowToken xs
-lex ['\'':x:'\'':xs] = ret (CharToken x) xs
-lex ['\'':'\\':x:'\'':xs] = case get x EscapeMap of
-	Just t = ret (CharToken t) xs
-	_ = err ("Unknown escape: \\" +++ toString x)
-lex ['-':t=:[x:xs]]
-| isDigit x = let (n, r) = span isDigit t in
-	ret (NumberToken (toInt $ toString ['-':n])) r
-| otherwise = ret DashToken  xs
-lex t=:[x:xs] = case get x SingleCharTokens of
-	(Just tok) = ret tok xs
-	Nothing
-	| x == '\n' = \i.lex xs (i+1)
-	| isSpace x = lex xs
-	| isDigit x = let (v, r) = span isDigit t in 
-		ret (NumberToken (toInt $ toString v)) r
-	| isAlpha x = let (v, r) = span isIdent t in ret (IdentToken v) r
-		with isIdent c = isAlphanum c || c == '_'
-	| otherwise = err ("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)