--- self =~ other

    ɽ other ȤΥޥåԤޤޥåХޥ
    ֤Υǥå򡢤Ǥʤ nil ֤ޤ

    other ʸǤäˤϤɽ˥ѥ뤷 
    self ФޥåԤޤ(ruby 1.8 feature: 
    ˡϿ侩ޤ(ٹ𤬽Ϥޤ) other ˤ String 
    ꤷƤ)

    ξȤ߹ѿ $~ ˥ޥå˴ؤ
    ꤵޤ

    other ɽǤʸǤʤ
        other =~ self
    Ԥޤ

