level 1
參考一下是你要的作法嗎?
$ irb
>> 1.class
=> Fixnum
>> 1.say
NoMethodError: undefined method `say' for 1:Fixnum
from (irb):2
from /home/user/.rvm/rubies/ruby-2.3.0/bin/irb:11:in `<main>'
>> class Fixnum
>> def say
>> puts 'one'
>> end
>> end
=> :say
>> 1.say
one
=> nil
2016年03月03日 00点03分