On Wed, Nov 02, 2005 at 10:57:37AM +0100, Daniel Bünzli wrote:
> This doesn't scale well, suppose that I want to extend Top_Bottom,  
> then I have a module called Top_Bottom_Myextension. I think 'include'  
> is a better mechanism if you need to extend modules.

Well that's if you want to add more functions to Top_Bottom; obviously
'include' would be the way forwards there (or the equivalent notion
where you mirror the definitions from the base module which is how
ExtLib works).  However consider a database layer:

  Database
  Database_Postgres
  Database_MySQL

Obviously '_' is the way to go here if you want multiple third parties
to provide database modules.  'include' wouldn't work at all here.

Rich.

-- 
Richard Jones, CTO Merjis Ltd.
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