From: Hal Fulton <hal9000@...>
Date: 2006-08-14T04:11:36+09:00
Subject: Re: PATCH to make internal Hash class retain order...

Daniel Schierbeck wrote:
> This is a question that has been raised during an earlier discussion of 
> this issue: What should this expression return?
> 
>   {:foo => 1, :bar => 2} == {:bar => 2, :foo => 1}
> 
> I don't think there's any way around it returning `true', but that would 
> decrease the usefulness of ordered hashes. One solution would be that 
> Hash#== returns true in such cases while Hash#eql? returns false, just as
> 
>   2 == 2.0    => true
>   2.eql? 2.0  => false

I once discussed this with Matz, and he said that two hashes
with the same key-value pairs would still be equal (if we
implemented an ordered hash, which is a big "if").

That doesn't bother me as long as I can iterate. I could
still do:

   h1.to_a == h2.to_a

to check equality with order taken into account.


Hal