Lazy evaluation in Ruby

Posted by fifigyuri on Stack Overflow See other posts from Stack Overflow or by fifigyuri
Published on 2010-03-17T10:26:36Z Indexed on 2010/03/17 10:31 UTC
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ruby

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lazy-loading

I have a situation for Ruby, where an object is possibly necessary to be created, but it is not sure. And as the creation of the object might be costly I am not too eager creating it. I think this is a clear case for lazy loading. How can I define an object which is not created only when someone sends a message to it? The object would be created in a block. Is there a way for simple lazy loading/initialisation in Ruby? Are these things supported by some gems, which provide different solutions for various cases of lazy initialisation of objects? Thanks for your suggestions!

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