$$var ??

[virtualdevl]

Can someone explain what that is and how it works? I have seen some code that has:

$name='blah';
$$name='blah2'; 

Thanks..

[galen]

it's a variable variable

$name='blah';
$$name='blah2'; 
echo $blah; 

this will echo blah2

the $name in $$name is assigned blah and you are left with $blah - setting $blah to 'blah2'

more info

[Mittineague]

It's a "variable variable". The PHP docs explain it better than I can, but it's something like
$name='blah';/* $name var = 'blah' */
$$name='blah2';/* same as $blah = 'blah2' */
I've seen them used for dynamically created variable names, but I've never used them myself.

[cranial-bore]

I find them useful in classes where I frequenty have to iterate over a group of object members, without having to access them each individually

e.g

class something
{
  public $name;
  public $email;
  public $phone;
  public $occupation;
  private $members = array('name', 'email', 'phone', 'occupation');

  private function trim_strings() {
     foreach($this->members as $v) {
        $this->$v = trim($this->$v);
    }
}

}