How to get a variable name as a string in PHP?

Question

Say i have this PHP code:

$FooBar = \"a string\";

i then need a function like this:

print_var_name($FooBar);

Answer 1

Many replies question the usefulness of this. However, getting a reference for a variable can be very useful. Especially in cases with objects and $this. My solution works with objects, and as property defined objects as well:

function getReference(&$var)
{
    if(is_object($var))
        $var->___uniqid = uniqid();
    else
        $var = serialize($var);
    $name = getReference_traverse($var,$GLOBALS);
    if(is_object($var))
        unset($var->___uniqid);
    else
        $var = unserialize($var);
    return "\${$name}";    
}

function getReference_traverse(&$var,$arr)
{
    if($name = array_search($var,$arr,true))
        return "{$name}";
    foreach($arr as $key=>$value)
        if(is_object($value))
            if($name = getReference_traverse($var,get_object_vars($value)))
                return "{$key}->{$name}";
}

Example for the above:

class A
{
    public function whatIs()
    {
        echo getReference($this);
    }
}

$B = 12;
$C = 12;
$D = new A;

echo getReference($B)."
"; //$B
echo getReference($C)."
"; //$C
$D->whatIs(); //$D