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Date: Sat, 08 Sep 2007 19:50:02 +0100
To: Stanislav Malyshev <stas@zend.com>
Cc: internals@lists.php.net, andi@php.net, dmitry@php.net
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Subject: Re:  Re: [PHP-DEV] constant folding optimization
From: nlopess@php.net (Nuno Lopes)

>> I made a patch to implement constant folding optimization in the  
>> Zend engine.
>> The patch is available at:  
>> http://web.ist.utl.pt/nuno.lopes/zend_constant_folding.txt
>
> I like the idea a lot, however I think this patch has one  
> significant downside - as far as I understand, it doesn't enable  
> constant expressions in constant contexts. I.e. I can do $a = 2+2  
> and get it evaluated but I can't do function foo($a = 2+2) or const  
> $a = 2+2. If we moved this to the parser level I think we could do  
> both.

Well we don't support that syntax at this moment. If you are saying  
that we could add support for such syntax.. it does seem a good idea,  
but in that case we would need to modify a few rules of the grammar  
(like adding a const_expr production, and allow static_scalar derive  
it, etc..).

If others agree with this syntax, I can take a look in implementing it.

Nuno