From: Nikolai Weibull <now@...>
Date: 2011-12-29T23:10:47+09:00
Subject: What’s the standard way of implementing #hash for value objects in Ruby?

Hi!

What’s the standard way of implementing #hash for value objects in Ruby?

For

class A
  def initialize(a, b, c)
    @a, @b, @c = a, b, c
  end
end

is it

def A.hash
  self.class.hash ^ @a.hash ^ @b.hash ^ @c.hash
end

or

def A.hash
  self.class.hash ^ [@a, @b, @c].hash
end

or is it something else?

No classes in the standard library use self.class.hash, but I think it
makes sense to use it.