Ruby Doc 作为测试,它失败了:
irb(main):001:0> 72.gcd 168 NoMethodError: undefined method `gcd' for 72:Fixnum from (irb):1
ruby 1.8.6 (2008-08-11 patchlevel 287) [i386-mswin32]
尝试
require 'rubygems' 72.gcd 168
require 'rational'