8.6. RegexString: Regex matching made simple

(Simon Marlow supplied the String Regex wrapper.)

For simple regular expression operations, the Regex library is a little heavyweight. RegexString permits regex matching on ordinary Haskell Strings.

The datatypes and functions that RegexString provides are:
data Regex              -- a compiled regular expression

        :: String       -- regexp to compile
        -> Regex        -- compiled regexp

        :: Regex        -- compiled regexp
        -> String       -- string to match
        -> Maybe [String] -- text of $1, $2, ... (if matched)