From: Benjamin Kudria <ben@...>
Date: 2010-07-08T09:29:15+09:00
Subject: Extending OpenStruct to be lazy and recursive

I'm trying to extend OpenStruct for an application I'm building, where
I'd like to access nested hashes as models. OpenStruct (in core) sounds
perfect for this, but I ran into two problems:

 - Recursion
    My hashes have nested hashes, and I want to convert *those* to
objects, too. I was able to solve this problem pretty easily, see the
to_self method in the linked code [1].

However, this made me run into the second problem - speed. I was loading
rather large documents, and it was taking quite a bit of time to go
through them, instantiating classes for everything. I though I'd make
the code lazy-load, using the lazy.rb [0]

However, I overrode some more core methods for OpenStruct, to create
promises, and demand them, but now the code simply produces incorrect
results.

In IRB, I do:
> LazyStruct.new({:a=>1, :b => 2}).a

But my result is 2, not 1. The code is here:
http://gist.github.com/467459

What could be going wrong? Any inishgt would be appreciatted. I'm using
Ruby 1.9.2-preview3

(Apologies for the Railsisms, this is part of a Rails project. The
classify method turns things into a string resembling a class, and
constantize turns that string into a constant - hopefully a class. This
code is bypassed in my simple example.)

0: http://github.com/mental/lazy

Thanks!
Benjamin Kudria
ben@kudria.net
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