Changeset 8724 for src/Pugs/Lexer.hs

Timestamp:

01/17/06 12:55:27 (3 years ago)

Author:

audreyt

Message:

* implemented \x[1,2,3,].

Files:

• src/Pugs/Lexer.hs (modified) (4 diffs)

src/Pugs/Lexer.hs

@@ -22 +22 @@
     rule, verbatimRule, literalRule,
     tryRule, tryVerbatimRule,
-    tryChoice,
+    tryChoice, ruleComma,
 
     ruleScope, ruleTrait, ruleTraitName, ruleBareTrait, ruleType,
@@ -61 +61 @@
 maybeParens :: CharParser st a -> CharParser st a
 maybeParens p = choice [ parens p, p ]
-
-maybeVerbatimBrackets :: CharParser st a -> CharParser st a
-maybeVerbatimBrackets p = choice [ verbatimBrackets p, p ]
 
 parens     :: CharParser st a -> CharParser st a
@@ -197 +194 @@
 
 -- | Backslashed non-alphanumerics (except for @\^@) translate into themselves.
-escapeCode      :: GenParser Char st Char
-escapeCode      = charEsc <|> charNum <|> charAscii <|> charControl <|> anyChar
+escapeCode      :: GenParser Char st String
+escapeCode      = ch charEsc <|> charNum <|> ch charAscii <|> ch charControl <|> ch anyChar
                 <?> "escape code"
+    where
+    ch = fmap (:[])
 
 charControl :: GenParser Char st Char
@@ -207 +206 @@
                     }
 
-charNum :: GenParser Char st Char                    
+-- This is currently the only escape that can return multiples.
+charNum :: GenParser Char st String
 charNum = do
-    code <- choice
-        [ decimal 
+    codes <- choice
+        [ fmap (:[]) decimal 
         , based 'o'  8 octDigit
         , based 'x' 16 hexDigit
         , based 'd' 10 digit
         ]
-    return . toEnum $ fromInteger code
+    return $ map (toEnum . fromInteger) codes
     where
     based ch num p = do
         char ch
-        maybeVerbatimBrackets (number num p)
+        choice [ verbatimBrackets (number num p `sepEndBy1` ruleComma)
+               , fmap (:[]) (number num p)
+               ]
+
+ruleComma :: GenParser Char st ()
+ruleComma = do
+    lexeme (char ',')
+    return ()
 
 number :: Integer -> GenParser tok st Char -> GenParser tok st Integer