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Date: Wed, 18 Apr 2012 00:10:15 +0200
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Subject: Re: [PHP-DEV] Variable-length args by reference
From: neufeind@php.net (Stefan Neufeind)

On 04/18/2012 12:02 AM, Stefan Neufeind wrote:
> Hi,
> 
> the topic of variable argument-lists for functions in connection with
> getting the parameters by reference came up. This is currently not
> possible with func_get_args(), though a "hack" with debug_backtrace() is
> possible.
> 
> How would you think about extending func_get_args() and func_get_arg()
> to allow for:
> 
> 	$args = func_get_args(FUNC_GET_ARGS_BY_REFERENCE);
> 	$arg0 = func_get_arg (0, FUNC_GET_ARGS_BY_REFERENCE);
> 
> (default would be FUNC_GET_ARGS_BY_COPY)
> 
> 
> Currently only the following "hack" works:
> 
> function calc()
> {
> 	$d = debug_backtrace();
>         $args = $d[0]['args'];
>         $args[0] *= 2;
>         $args[1] *= 2;
> }
> 
> $a = 5;
> $b = 7;
> var_dump ($a, $b);
> calc(&$a, &$b);
> var_dump ($a, $b);

Hmm, that example also only works because of the call-time
pass-by-reference? *sigh*
Sorry, I forgot those ampersands in the call to calc(). Doesn't work
without.

I hope the idea is clear though. Any chance we might make this possible
through func_get_args()?


Regards,
 Stefan