From: dblack@...
Date: 2006-04-19T22:20:37+09:00
Subject: Re: interested in metaprogramming?

Hi --

On Wed, 19 Apr 2006, Gregory Seidman wrote:

> On Wed, Apr 19, 2006 at 06:31:47PM +0900, chiaro scuro wrote:
> } two people is already a crowd to me :-)
> }
> } I'll let you know when I post more about metaprogramming and DSLs.
>
> I only skimmed what you've written so far, but I noticed that you've used
> class_eval. It is preferable to avoid any form of eval whenever possible.
> In your post you can replace...
>
> Array.class_eval  do
>  synonym :size => [ :count, :n_elements ]
> end
>
> ...with...
>
> Array.send(:synonym, :size => [ :count, :n_elements ])
>
> ...to avoid the class_eval.

I don't think instance_eval and class_eval, in their block forms, have
the same issues as plain eval(string).  class_eval is really just a
closure cousin of the class keyword.


David

-- 
David A. Black (dblack@wobblini.net)
Ruby Power and Light, LLC (http://www.rubypowerandlight.com)

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