--- prec(klass)

    self  klass Ѵ̤֤ޤǥե
    Ǥ klass.induced_from(self) ƤӽФη
    ̤֤ޤ

    ٥饹ȤȤ߹ߥ饹
    Precision.induced_from ѹΤǤϤʤ 
    prec κб٤Ǥ

