Posted by Jochem Maas on 09/20/05 12:13

Jasper Bryant-Greene wrote:
> Lester Caine wrote:
>
>> I suppose the REAL questions was - "Why was using the function in this
>> way a 'bad practice', is there any way that it could be made a 'good
>> practice' since the intent is so obvious?"
>> I understand the new checks, but I don't see that the original was
>> particularly 'bad' - only that under some conditions it might cause a
>> problem?
>>
>
> Basically, in PHP, a reference (such as what key() takes as a parameter
> [1]) can only point to an actual variable, not directly to the result of
> a function. So you have to assign the output of the function to a
> variable first.
>
> From the PHP manual [2]:
> | the following examples of passing by reference are invalid:
> |
> | foo(bar()); // Produces fatal error since PHP 5.1.0
> | foo($a = 5); // Expression, not variable

wtf, Im now officially confused (before I suffered unofficially :-)

if foo() expects one args by reference then why is doing:

foo($a = 5);

...wrong? I always thought that the expression (in this form) 'returns'
the variable? or does it need to be:?

foo( ($a = 5) );

in fact I'm pretty sure that an example (like this) of a fix for
the 'bad coding' practice that is now throwing notices/errors was
given on internals-php quite recently.

I can understand that the following are wrong:

foo(5); // not sure this is wrong.
foo(bar());

but how is:

foo(($a = 5));

different from?:

$a = 5; foo($a);


> | foo(5); // Produces fatal error
>
> Whether this is the optimal behaviour has been the subject of recent
> debate on this list [3]. Rasmus states that the current behaviour of
> throwing a fatal error will be changed to a notice.
>
> [1] http://php.net/key
> [2] http://php.net/language.references.pass
> [3] http://marc.theaimsgroup.com/?l=php-general&m=112689425109173&w=2

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