From: 7stud -- <bbxx789_05ss@...>
Date: 2009-03-12T20:40:56+09:00
Subject: Re: how to get all attributes in an element

Phlip wrote:
> Naresh Ramaswamy wrote:
> 
> Next, the attributes come in a Hash, and this has a BUG (!) which will 
> be FIXED
> (!) in the next Ruby versions. It can't preserve the order you inserted 
> its keys.
>

Hmm.  A bug is when a language doesn't operate as described:

----
p. 46, pickaxe 2:

[a hash's] elements are not ordered, so you can not easily use a hash as 
a stack or a queue.

p. 492

The order in which keys and/or values are returned by the various 
iterators over hash contents may seem arbitrary and will generally not 
be in insertion order.
----

$ ri Hash

------------------------------------------------------------ Class: Hash
     A +Hash+ is a collection of key-value pairs. It is similar to an
     +Array+, except that indexing is done via arbitrary keys of any
     object type, not an integer index. The order in which you traverse
     a hash by either key or value may seem arbitrary, and will
     generally not be in the insertion order.

     Hashes have a _default value_ that is returned when accessing keys
     that do not exist in the hash. By default, that value is +nil+.

------------------------------------------------------------------------


Also, in many other languages dictionaries or associative arrays are 
unordered collections.
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