From: "Ara.T.Howard" <ahoward@...>
Date: 2004-03-04T07:04:44+09:00
Subject: Re: why are Hashes so unsorted? what's your solution?

On Thu, 4 Mar 2004, Ruby Baby wrote:

> Thanks for your help and advice, everyone.
> 
> The description, below, is correct.
> 
> Since I learned PHP first, I started heavily relying on this,
> not knowing it was a PHP quirk.
> 
> So when I learned Ruby, I assumed "Hash" was the same as PHP's
> "associative array" and was surprised they weren't in order.

there ARE associtive arrays in ruby if you want...

  irb(main):001:0> a=[[:k,:v], [:foo,:bar]]
  => [[:k, :v], [:foo, :bar]]
  irb(main):002:0> a.assoc :k
  => [:k, :v]
  irb(main):003:0> a.assoc :foo
  => [:foo, :bar]

-a
> 
> 
> 
> > PHP blurs the lines between hashes, 
> > arrays, whatever you want to call them. There is just one construct, 
> > which they call an Array. Each item in the array can have both a hash 
> > key (a string) and an index (an integer). if you write "myarray['test'] 
> > = item", an index automatically gets created in addition to the hash 
> > key.
> > Additionally, PHP arrays have an order, which is not necessarily the 
> > same as the order given by the indices. In fact, it is *very* often 
> > different. Usually it is the order in which items were added to the 
> > array. Calling "each()" iterates over the array in the hidden order. If 
> > you want, you can sort the array/hash by the internal/hidden ordering, 
> > and indices and hashes are unchanged, but iterating over it with 
> > "each()" is different.
> > 
> > Of course, this sounds confusing all thrown together like this, but it 
> > really isn't that bad. You can do some nifty tricks, all because of the 
> > strange hybrid php hash/lists. :)
> 
> 
> 

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