What's =& for?

[Kudose]

I was looking into some Pear files and noticed some statements like:

$res =& $db->query('DELETE * FROM clients');

What's the =& about? Does it pass a reference of the $db objects result to $res?

[NogDog]

Here's what the manual says about it. (I won't claim to entirely understand it and why you'd want to do it, but then I never really understood why people wanted to use pointers in C. 🙂 )

[Kudose]

NogDog wrote:

... I never really understood why people wanted to use pointers in C. ...

Me either! That's why I quit trying to learn it ... 🙁

[Kudose]

I thought I heard something about PHP5 taking care of referencing for the developer.

i.e. if you forget to use one where you needed, it was okay.

Have you heard anything like that?

[Nugen]

Kudose wrote:

I was looking into some Pear files and noticed some statements like:

$res =& $db->query('DELETE * FROM clients');

What's the =& about? Does it pass a reference of the $db objects result to $res?

$res is a reference for $db->querys results. meaning if the results of $db->query change $res will reflect them as $res is just an alias to the real information of the object.

whoever wrote it most likely uses C as there really isn't a major need for this unless you're working with lots of information and don't want to have duplicate variables stored at once. (having variables, objects, and arrays of duplicate information just create more overhead - if this is small amounts of information its not a big deal as it will be cleared once the execution of the script ends these are cleared.

In C if an application continues running it will continue to store these details until they are unset / altered or destroyed. (taking up more memory when unneeded in a consistent state).

[Kudose]

That's what I figured. Just wanted to make sure though.

Thanks you two. 🙂

[NogDog]

As to your PHP5 question, I believe the change that has some impact here is that in 5 if a function returns an object, it now automatically returns what is, in effect, a reference; so having a function return by reference would be redundant if what it is returning is an object.