[SOLVED] What does the & symbol do when put infront of another variable?

[Demonic]

I seen this a lot in IPB and vBulletin coding, what does this do?

[btherl]

It creates a reference.  You should stay away from these unless you know what you're doing

 

A simple example:

 

$a = 5;
$b = &$a;
$b = 2;
print "a now has value $a\n";

 

When you make $b a reference to $a, the variables become shared.  Changes to either one will affect both.  Only one copy of the actual data is stored.

 

PS In general it's a bad idea to use references to try to save memory.  PHP already has mechanisms that save memory in most common situations where variables are copied.

[Demonic]

oh shit, like a refernces/pointers in C/C++?

[trq]

Exactly.

[Demonic]

Thats pretty cool  .