From: lasitha <lasitha.ranatunga@...>
Date: 2009-03-12T16:10:42+09:00
Subject: Re: change (and update) values of hash

On Thu, Mar 12, 2009 at 12:06 PM, Jason Lillywhite
<jason.lillywhite@gmail.com> wrote:
>
>> This is much easier:
>> h.each {|k, v| h[k] = v * 2 }
>
> thank you.
>
> I was told it could be bad to change values during iteration. That is
> why I proposed doing replace. what do you think?

There was a recent thread about this:
http://www.nabble.com/Iterating-a-changing-Hash-under-1.9.1-td22023417.html

I believe assigning values to existing keys is safe.

If in doubt, iterate over the keys instead:
h.keys.each {|k| h[k] = h[v] * 2 }

solidarity,
lasitha.