A regular expression matcher By Rob Pike and Brian Kernighan (2007)

    int matchstar(int c, char *regexp, char *text)
    {
        do {    /* a * matches zero or more instances */
            if (matchhere(regexp, text))
                return 1;
        } while (*text != '\0' && (*text++ == c || c == '.'));
        return 0;
    }

I recommend implementing this as an exercise, rarely do you see that much classic CS theory put to a practical use in one place.

    match :: String -> String -> Bool
    match ('^':rest) text     = matchLocal rest text
    match rex        (c:rest) = matchLocal rex (c:rest) || match rex rest
    match _          _        = False
 
    matchLocal :: String -> String -> Bool
    matchLocal []            _         = True
    matchLocal "$"           []        = True
    matchLocal (c:'*':restR) (t:restT) = c == t && matchLocal restR (starSkip c (t:restT))
    matchLocal (r:restR)     (t:restT) = (r == '.' || r == t) && matchLocal restR restT
    matchLocal _             _         = False
 
    starSkip :: Char -> String -> String
    starSkip c (t:rest) = if c == t then starSkip c rest else t:rest
    starSkip _ []       = []

Adding a few lines of css (setting body width, font-size to 16, line-height to 1.4, Georgia for font and larger font size for headings ) makes for a decent reading experience.

http://imgur.com/a/KtaEC/