Changeset 13183 for src/Pugs/Lexer.hs

Timestamp:

09/11/06 16:31:53 (2 years ago)

Author:

audreyt

Message:

* Add support for character name escapes:

say "\c[LATIN CAPITAL LETTER Y]";

With Perl 5 embedding, the full Unicode range is supported via
charnames.pm. Without Perl 5 embedding (e.g. in "make ghci"),
only codepoints in the range 0x00-0xFF are supported.

Note: Now Perl5 embedding is on by default, we can implement
more "core" Pugs functionalities this way, instead of maintaining
huge amount of duplicate information. (Encode.pm comes to mind.)

Files:

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

src/Pugs/Lexer.hs

@@ -31 +31 @@
 import Pugs.Types
 import Pugs.Parser.Types
+import Pugs.Parser.Charnames
 
 identStart, identLetter :: RuleParser Char
@@ -265 +266 @@
 
 charControl :: RuleParser Char
-charControl     = do{ char 'c'
-                    ; code <- upper <|> char '@'
-                    ; return (toEnum (fromEnum code - fromEnum '@'))
-                    }
+charControl = do
+    char 'c'
+    code <- upper <|> oneOf "@["
+    case code of
+        '[' -> do
+            charName <- many (satisfy (/= ']'))
+            char ']'
+            case nameToCode charName of
+                Just c  -> return (chr c)
+                _       -> error $ "Invalid unicode character name: " ++ charName
+        _   -> return (toEnum (fromEnum code - fromEnum '@'))
 
 -- This is currently the only escape that can return multiples.
@@ -483 +491 @@
                     
 fractExponent n = do{ fract <- fraction
-                    ; expo  <- option 1.0 exponent'
+                    ; expo  <- option (1.0 :: Double) exponent'
                     ; return ((fromInteger n + fract)*expo)
                     }
@@ -493 +501 @@
 fraction        = do{ char '.'
                     ; digits <- many1 digit <?> "fraction"
-                    ; return (foldr op 0.0 digits)
+                    ; return (foldr op (0.0 :: Double) digits)
                     }
                     <?> "fraction"
                 where
-                    op d f    = (f + fromIntegral (digitToInt d))/10.0
+                    op d f    = (f + fromIntegral (digitToInt d)) / (10.0 :: Double)
                     
 exponent'       = do{ oneOf "eE"