Should the implementation of "==" in Ruby check the type?

Question

I want to implement ==for the ruby class. I can do

def ==(o)
  o.respond_to?(:id) && self.id == o.id
end

or

def ==(o)
  o.is_a?(Foo) && self.id == o.id
end

According to this article, it seems that the first meaning makes sense. If I implemented eql?, I would do the latter. It's right?

+5

Amir raminfar May 22 '12 at 18:50

1 answer

tadman · Accepted Answer · 2012-05-22T18:56:38+0000

It depends on whether you are being compared with any object or with a particular type. The second form is specific, the first is general.

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