Override == operator in Ruby

ruby overriding equality
lynks picture lynks · Jun 25, 2012 · Viewed 20.1k times · Source

According to the docs, Array.include? uses the == comparison on objects. I come from Java where such things are (usually) done with .equals() which is easy to override for a particular object.

How can I override == in Ruby to allow me to specify the behaviour of Array.include? for my particular object?

Many thanks.

Answer

sepp2k picture sepp2k · Jun 25, 2012

In Ruby == is just a method (with some syntax sugar on top allowing you to write foo == bar instead of foo.==(bar)) and you override == just like you would any other method:

class MyClass
  def ==(other_object)
    # return true if self is equal to other_object, false otherwise
  end
end

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