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Date: Sun, 03 Apr 2005 14:18:29 +0200
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To: Zeev Suraski <zeev@zend.com>
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Subject: Re: [PHP-DEV] __autoload() enhancement
From: php@hristov.com (Andrey Hristov)

Zeev Suraski wrote:
> All,
> 
> One problem that became apparent after the introduction of __autoload(), 
> is that different pieces of code, sometimes coming from different 
> sources, may want to declare this function in a different way.  Today, 
> __autoload() is treated like any other function, so it's impossible to 
> re-declare it.
> 
> Marcus tried to solve it by introducing an __autoload() wrapper in SPL.  
> Personally I think it's probably not the right way to go, but that's 
> beside the point right now.
> 
> What I'd like to suggest is a change in the behavior of __autoload(), so 
> that multiple __autoload()'s could be defined.  Essentially, declaring 
> __autoload() would in fact add the function to the list of functions 
> that are called in case a missing class is referenced.  However, it will 
> not actually place a function named __autoload() in the PHP function 
> table.  That way, it would be possible to declare multiple 
> __autoloads(), and have all of them called when a missing class is spotted.
> 
> The two issues with this solution are:
> 
> 1.  It will be impossible to use the standard means to determine whether 
> __autoload() is declared or not.  I don't think that's a very important 
> issue but it's there nonetheless.
> 2.  We need to determine what makes sense as far as calling order if we 
> have more than one __autoload().  My guess would be calling them in the 
> order they were registered, and checking whether the class was defined 
> after each one (if it was - stop).
> 
> That solution maintains downwards compatibility (almost, other than 
> issue #1).
> 
> Thoughts?
> 
> Zeev
> 
  Hi Zeev,
the idea one __autoload() may not be capable of loading therefore the next
one in the chain should be executed to try to load/define the needed code.
bool(false) returned from __autoload() means try with the next in the chain,
bool(true) everything went fine skip the rest of the queue.

Andrey