1089a1090,1094
    > (xdef 'regexp regexp)
    > (xdef 'r-match regexp-match)
    > (xdef 'r-match-pos regexp-match-positions)
    > (xdef 'r-replace regexp-replace)
    > 

    arc> (= r (regexp "(-[0-9]*)+"))
    #rx"(-[0-9]*)+"
    arc> (r-match r "a-12--345b")     
    ("-12--345" "-345")