@@ -81,3 +81,8 @@ isHexDigit x = elem (toUpper x) hexChars where
81||| Returns true if the character is an octal digit.
81||| Returns true if the character is an octal digit.
82isOctDigit : Char -> Bool
82isOctDigit : Char -> Bool
83isOctDigit x = (x >= '0' && x <= '7')
83isOctDigit x = (x >= '0' && x <= '7')
85+||| Returns true if the character is a control character.
86+isControl : Char -> Bool
87+isControl x = (x >= '\x0000' && x <= '\x001f')
88+ || (x >= '\x007f' && x <= '\x009f')