X-Git-Url: https://git.martlubbers.net/?a=blobdiff_plain;f=lex.icl;h=6cb2e922e4615fb487f080e6372721b789d5633f;hb=74b900cf6db033a51e177f7f85d835dae44217e5;hp=f050062d7f172760b708a867a469d06cba3dc75c;hpb=19c5f39c61f1692641570dc3cf13360e7dff5cdf;p=cc1516.git

diff --git a/lex.icl b/lex.icl
index f050062..6cb2e92 100644
--- a/lex.icl
+++ b/lex.icl
@@ -1,3 +1,126 @@
-module lex
+implementation module lex
 
-Start = "Hello World!\n"
+import Control.Monad, Control.Applicative
+import Data.Either, Data.Func, Data.Void
+import Data.Map
+from StdFunc import o
+import StdBool
+import StdList
+import StdChar
+import StdString
+import StdTuple
+
+import yard
+import AST
+
+:: LexItem
+	= LexToken Int TokenValue
+	| LexSpace Int Int
+	| LexNL
+	| LexEOF
+	| LexItemError String
+
+escapes :: Map Char Char
+escapes = fromList [('a', toChar 7), ('b', '\b'), ('f', '\f'), ('n', '\n'),
+	('r', '\r'), ('t', '\t'), ('v', '\v'), ('\'', '\''), ('"', '"')]
+
+lexer :: [Char] -> LexerOutput
+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 <|>
+    lexKw "Let" LetToken <|>
+	//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 <|> lexWord "\\" BackslashToken <|>
+	//Number and identifier tokens
+	lexString <|> 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 get char escapes of
+				Just e = LexToken 4 (CharToken e)
+				Nothing = LexItemError $ "Unknown escape: " +++ toString char
+
+		lexString :: Parser Char LexItem
+		lexString = item '"' *> (
+			many (
+				(satisfy (\c->c <> '"' && c <> '\\')) <|>
+				(item '\\' *> top >>= \char->case get char escapes of
+					Just e = pure e
+					Nothing = empty)
+			))<* item '"' >>= \cs-> pure $ LexToken (length cs) (StringToken cs)