From: Siep Korteling <s.korteling@...>
Date: 2008-10-02T06:58:00+09:00
Subject: Re: Ordered hash hack for < ruby 1.9?

Ben Johnson wrote:
> Lex Williams wrote:
>> this sorts them alphabetically , not by insertion order.
> 
> I didn't need them by insertion order, just to be consistent. I 
> apologize if I made that unclear.
> 
> Also, I am not testing a hash, I am testing a method that returns a 
> string. That string is built by iterating over a hash.
> 
> Thanks.

This code fills a hash and then iterates the hash to build a string.

h={}
("a".."z").each{|i| h[i] = i}
10.times do
  res = h.inject(""){|str, pair| str<<pair[1]}
  puts res
end

The string is always "vkwlaxmbynczodpeqfrgshtiuj" on my machine. There 
is no visible logic, but it is predictable and testable. However, the 
test may fail when you install the next ruby version, or perhaps when 
run on a another platform.
I don't know why your code behaves differently, but if the insertion 
order in the hash is not predictable (threads ?), then an ordered hash 
won't help.

regards,

Siep
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