[project @ 2004-08-13 13:04:50 by simonmar]

[ghc-hetmet.git] / ghc / compiler / parser / Ctype.lhs

diff --git a/ghc/compiler/parser/Ctype.lhs b/ghc/compiler/parser/Ctype.lhs
index 414aa4f..d97d5e0 100644 (file)
--- a/ghc/compiler/parser/Ctype.lhs
+++ b/ghc/compiler/parser/Ctype.lhs
@@ -9,12 +9,16 @@ module Ctype
        , is_lower      -- Char# -> Bool
        , is_upper      -- Char# -> Bool
        , is_digit      -- Char# -> Bool
+
+       , is_hexdigit, is_octdigit
+       , hexDigit, octDecDigit
        ) where
 
 #include "HsVersions.h"
 
 import DATA_INT                ( Int32 )
 import DATA_BITS       ( Bits((.&.)) )
+import Char            ( ord, chr )
 \end{code}
 
 Bit masks
@@ -48,6 +52,28 @@ is_upper  = is_ctype cUpper
 is_digit  = is_ctype cDigit
 \end{code}
 
+Utils
+
+\begin{code}
+hexDigit :: Char -> Int
+hexDigit c | is_digit c = ord c - ord '0'
+           | otherwise  = ord (to_lower c) - ord 'a' + 10
+
+octDecDigit :: Char -> Int
+octDecDigit c = ord c - ord '0'
+
+is_hexdigit c
+       =  is_digit c 
+       || (c >= 'a' && c <= 'f')
+       || (c >= 'A' && c <= 'F')
+
+is_octdigit c = c >= '0' && c <= '7'
+
+to_lower c 
+  | c >=  'A' && c <= 'Z' = chr (ord c - (ord 'A' - ord 'a'))
+  | otherwise = c
+\end{code}
+
 We really mean .|. instead of + below, but GHC currently doesn't do
 any constant folding with bitops. *sigh*