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To: "Andrew Brampton" <andrew@bramp.freeserve.co.uk>,
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Date: Mon, 17 Sep 2007 14:45:04 +0100
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Subject: Re: [PHP-DEV] RFC: mark functions as const for possible optimizations
From: nlopess@php.net ("Nuno Lopes")

> I had a quick question about this. When would strlen('abcd') be execuated? 
> Say I had the code:
>
> $a = false; // This set by external input
> if ( $a )
>  $b = strlen('abcd');
>
> Would the optimizer work out the length before the program starts to run? 
> Or would the optimizer wait until it knows the strlen is going to be 
> called then convert it to the constant 4?

That's not my problem.. My RFC is about making the information available, 
not writing the optimizer itself (at least for now). With a naive optimizer, 
strlen() would be called, yes.

> I could see the optimizer "constifying" many function calls which will 
> never get called.

that's not a problem since you would use a cache..

Nuno