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glenjamin · 2011-04-03 · Original thread
I'm not really sure, there's an O'reilly book "Metaprogramming Ruby" ( which i flicked through once. It seemed to mostly dicuss how ActiveRecord works. At the point I had access to a copy I was already pretty familiar with the concepts, so can't really say how good the book actually is.

I mostly picked things up by reading code and some blog posts whenever I came across an odd idiom.

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