From: Charles Oliver Nutter <charles.nutter@...>
Date: 2009-02-05T06:49:20+09:00
Subject: [ruby-core:21836] Re: 1.9 Bug Report

Yusuke ENDOH wrote:
> On the other hand, 1.9's hash is insertion-ordered.  An newly inserted
> key will certainly appear at the last of the order.
> So inserting new keys during an iteration makes the iteration infinite
> loop.
...
> $ ruby19 test.rb
> [{1=>nil, 2=>nil}, 1]
> [{2=>nil, 1=>nil}, 2]
> [{1=>nil, 2=>nil}, 1]
> [{2=>nil, 1=>nil}, 2]
> [{1=>nil, 2=>nil}, 1]
> [{2=>nil, 1=>nil}, 2]
> [{1=>nil, 2=>nil}, 1]
> [{2=>nil, 1=>nil}, 2]
> [{1=>nil, 2=>nil}, 1]
> [{2=>nil, 1=>nil}, 2]

JRuby behaves the same way.

- Charlie