From: "William James" <>
Date: 2009-02-14T04:28:39+09:00
Subject: Re: If you are unhappy with the direction of Ruby 1.8.7+, respond

James Coglan wrote:

> [Note:  parts of this message were removed to make it a legal
> post.]
> 
> > 
> > > Regardless of whether they're supposed to, the Rubies
> > > I've used before 1.8.7 actually do iterate in insertion
> > > order.
> > 
> > NO THEY DO NOT. It is the nature of a regular hashtable that
> > the order of entries in its internal data structures depends
> > only on the hash function and its inputs. It doesn't know
> > anything about the order of entries in your hash literal.
> > 
> > I've shown you examples using Ruby *1.8.6* that clearly
> > demonstrate that it gives a **** about order of appearance
> > in a literal, or insertion order.
> 
> 
> 
> I'm really not up for a slanging match so let me just say
> that, in code I've written, Ruby < 1.8.7 has demonstrated the
> behaviour I described. This may be a fluke or a bug, in which
> case I will investigate further and file bugs if necessary.
> What I do know is that I've had code in a library released
> over 2 years ago and used by a fair number of people relying
> on this behaviour and heard no complaints until 1.8.7
> arrived.

It's bad to write code that works by accident.
It's good to write code that works by design.

>            I realise that hashtables are not ordered in 1.8

Normal hash-tables are ordered nowhere, no-how, and no-way.

>  and
> have since made my code more robust.  I'm not questioning
> your examples -- you can but experiment to see what works --
> and I will try to extract the code from my project that
> demonstrates my point when I have some time.
> 
> I'm not the least bit interested in who's right or wrong or
> in berating the Ruby code devs or indeed anyone else, and was
> hoping for a productive discussion, not people repeatedly
> asserting that I don't know how a hash table works

Do you understand how a hash-table works?  Have you ever
implemented one?  Have you studied hash-table code written
by someone else?

A 9-year-old boy wanted to keep track of the color of his
toys.  He wrote "car: red" on a piece of paper which he then
put in a bag.  Then he did the same with "airplane: silver"
and "ball: blue".  Days later, he decided to review the data.
He reached into the bag and pulled out a slip.  It didn't
say "car"!  It was the slip with the color of the ball!
The slips were coming out in the wrong order!
Devestated, he began crying and ran to his mommy.

>                             and trying
> to shut me up. When I've time I'll see if what I have is a
> Ruby bug or something else. Until then I'm canning this
> conversation.