From: "David A. Black" <dblack@...>
Date: 2007-10-26T03:59:43+09:00
Subject: Re: Need help understanding metaclassing

Hi --

On Fri, 26 Oct 2007, Robert Dober wrote:

> Notwithstanding the answers you got already and they are very worthy
> indeed I would like to add my grain of salt.
> I like to see metaprogramming a little bit as program generation
>
> A.module_eval {

s/{/do/ :-)

>   define_method :b do |n| 42*n end
> end
>
> is just the same as the following of course
> class A
>   def b n
>      42*n
>   end
> end

It's very key, though, that define_method takes a block, since that
gives the method body access to local variables.


David

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