From: Florian Gilcher <flo@...>
Date: 2011-07-01T20:23:29+09:00
Subject: Re: How to order Structs based on two fields


On Jul 1, 2011, at 12:55 PM, Iņaki Baz Castillo wrote:

> 2011/7/1 Iņaki Baz Castillo <ibc@aliax.net>:
>> I expected that the following could work:
>> 
>>  array.sort_by{|entry| entry.a or entry.b}
>> 
>> but it generates:
>> 
>>   [kk1, kk2, kk3, kk4]
>> 
>> so obviously it does not work. I'm not very used to Enumerable.sort_by
>> method, any tip please?
> 
> Maybe it would be better to use "class KK" rather than an struct, and
> then define <=> method for KK class (and include Enumerable module)?

You can have both:

KK = Struct.new(:a, :b) do
  include Enumerable

  def <=>
    #...
  end
end

Regards,
Florian