X-Git-Url: https://git.martlubbers.net/?a=blobdiff_plain;f=lex.icl;h=21a29e92a03aefbd7f7189c8795501dbfb963215;hb=a8130cb2a970f385a7da0e2a8f7b02c1cb1a7639;hp=0adb20c879a4b3492df770199df3ef302989af9b;hpb=f4ee031491f6d753513b03f46a602321569e1114;p=cc1516.git

diff --git a/lex.icl b/lex.icl
index 0adb20c..21a29e9 100644
--- a/lex.icl
+++ b/lex.icl
@@ -1,72 +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
+from StdFunc import o
 import StdBool
 import StdList
 import StdChar
-import qualified Text
+import StdString
 
-SingleCharTokens :: Map Char Token
-SingleCharTokens = fromList [
-	('(', BraceOpenToken), (')', BraceCloseToken), ('{', CBraceOpenToken),
-	('}', CBraceCloseToken), ('[', SquareOpenToken), (']', SquareCloseToken),
-	(',', CommaToken), (':', ColonToken), (';', SColonToken),
-	('.', DotToken), ('+', PlusToken), ('*', StarToken), ('/', SlashToken),
-	('%', PercentToken), ('=', AssignmentToken), ('<', LesserToken),
-	('>', BiggerToken), ('!', ExclamationToken)]
+import yard
 
-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]
+lexer r = case runParser (lexProgram 1 1) r of
+	(Right p, _) = Right p
 	(Left e, _) = Left e
 
-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 ['-':t=:[x:xs]]
-| isDigit x = let (i, r) = span isDigit t in (Right (NumberToken ['-':i]), r)
-| otherwise = (Right DashToken, xs)
-lex t=:[x:xs] = case get x SingleCharTokens of
-	(Just tok) = (Right tok, xs)
-	Nothing
-	| isSpace x = lex xs
-	| isDigit x = let (i, r) = span isDigit t in (Right (NumberToken i), r)
-	| isAlpha x = let (i, r) = span isIdent t in (Right (IdentToken i), r)
-		with isIdent c = isAlphanum c || c == '_'
-	| otherwise = (Left ("Unexpected character: " +++ toString x), [])
+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, column=column, token=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)
+
+		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)