[whatwg] native ordered dictionary data type in web storage draft

Patrick Mueller pmuellr at muellerware.org
Tue Apr 14 10:54:15 PDT 2009

James Graham wrote:
> Aryeh Gregor wrote:
>> On Tue, Apr 14, 2009 at 10:18 AM, Patrick Mueller
>> <pmuellr at muellerware.org> wrote:
>>> This is the first time I've seen the requirement for such a beast.  
>>> You can
>>> understand the desire for it, given the context, but still.  Does 
>>> anything
>>> else in JavaScript make use of such a data structure?
>> It says that JavaScript should just use Object.  Isn't that,
>> essentially, an ordered dictionary?
> Yes. Indeed there are compatibility requirements for the ordering of 
> ordinary user-created Object Objects in web browser implementations; the 
> order of enumeration must be the same as the order of insertion of the 
> properties.

Interesting.  I guess this is a "JavaScript in web browser 
implementation" difference from the "JavaScript spec".  Following the 
links in jresig's blog post


in the "for loop order" section.

Still doesn't seem like it makes sense to go ahead and build 
dependencies on this (unfortunate, IMO) behavior.

Patrick Mueller

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