[RESOLVED] Get the name of a variable at runtime?

Hexxx

Is there anyway to get the name of a variable at runtime? What's making it more difficult is I want to get the name of a variable before it was passed into a function. For example, in this code which uses

function show ($object)
{
	echo "showing...<br>";
	echo "<pre>";
	var_dump ($object);
	echo "</pre><br>";

}

I would to be able to see the name of the variable that show was called on, say I did show ($abba);

The first like would be

showing $abba...

I read the Variable variable notes in the manual, but it sounded too confusing!

bradgrafelman

I don't normally dish out free code, but this sounded like a challenge to me and here's what I came up with:

function show(&$test) {
	if(!is_scalar($test)) {
		echo 'ERROR: show() - variable type not supported';
		return FALSE;
	}

$original = $test;
$test .= uniqid('FINDME');

if(($name = array_search($test, $GLOBALS)) && ($name === NULL || $name === FALSE)) {
	echo 'ERROR: show() - variable name could not be found';
	return FALSE;
} else {
	$test = $original;
	return $name;
}
}

show() returns the name of the variable (assuming it could find it). Note that the variable must be a scalar value. For more information on what a scalar value is, look at [man]is_scalar/man. You can probably extend this function to include arrays (at least), but I didn't go that far.

laserlight

Why do you want to do this?

bradgrafelman

laserlight wrote:
Why do you want to do this?

Dang it, I knew I forgot something.

To continue on with my previous post (inspired by laserlight's): As you can see, it is a pretty complex, hit-or-miss type of process that I came up with. Is there a better way? I don't know... probably, since I'm not the wisest coder who ever lived, but still... I've never had a need to know the name of a supplied variable as you've illustrated. If you're asking because you want to alter that variable, all you need to do is pass it in reference (as, incidentally, my example show() function does).

Hexxx

Ok, I wanted to know the name of the variable because of the show function I was coding up there. When I use them (the show() )on alot of similar variables (namely arrays) it can be confusing to know which one is which, so I want the name along with it to help in debugging.

bradgrafelman

Can't you just ammend your code like so:

show($theArray, 'theArray');

As I said, my code won't work on arrays (without some modifications) so you'd require an even more complex workaround. Specifying the variable's name you're using as the second parameter, however, would be much easier.

Hexxx

Ok, that was true!
That's what I get for thinking too much!