From: Ryan Davis <ryand-ruby@...>
Date: 2011-12-30T17:44:24+09:00
Subject: Re: What’s the standard way of implementing #hash for value objects in Ruby?


On Dec 29, 2011, at 21:25 , Josh Cheek wrote:

> On Thu, Dec 29, 2011 at 5:47 PM, Nikolai Weibull <now@bitwi.se> wrote:
> 
>> 
>> I seem to have failed in communicating what I’m after.  I wasn’t after
>> different ways of implementing #hash, I was after the golden standard
>> of #hash implementations for value objects.  So, again, what’s the
>> standard way of implementing #hash for value objects in Ruby?
>> 
>> If there isn’t one, perhaps one should be agreed upon?
>> 
>> 
> If there is one, I don't know what it is, which implies there isn't one.
> 
> I usually just delegate to one of my attributes' hash methods (e.g. for a
> user, I might use its user's name's hash). I'm not sure what advantage
> would be gained by establishing a standard.

You should be doing the same attributes you use in an equality test. I usually throw all the attributes in an array and ask for it's hash.