Is there a way to get the name of a variable? PHP - Reflection

Question

I know this is not exactly reflection, but kind of. I want to make a debug function that gets a variable and prints a var_dump and the variable name.

Of course, when

Answer 1

This is late post but I think it is possible now using compact method

so the code would be

$a=1;
$b=2;
$c=3

var_dump(compact('a','b','c'));

the output would be

array (size=3)
'a' => int 1
'b' => int 2
'c' => int 3

where variable name a, b and c are the key

Hope this helps

Answer 2

i've had the same thought before, but if you really think about it, you'll see why this is impossible... presumably your debug function will defined like this: function debug($someVar) { } and there's no way for it to know the original variable was called $myvar.

The absolute best you could do would be to look at something like get_defined_vars() or $_GLOBALS (if it were a global for some reason) and loop through that to find something which matches the value of your variable. This is a very hacky and not very reliable method though. Your original method is the most efficient way.

Answer 3

Not elegantly... BUT YOU COULD FAKE IT!

• 1) Drink enough to convince yourself this is a good idea (it'll take a lot)
• 2) Replace all your variables with variable variables:

$a = 10
//becomes
$a = '0a';
$$a = 10;

• 3) Reference $$a in all your code.
• 4) When you need to print the variable, print $a and strip out the leading 0.

Addendum: Only do this if you are

• Never showing this code to anyone
• Never need to change or maintain this code
• Are crazy
• Not doing this for a job
• Look, just never do this, it is a joke

Answer 4

Bit late to the game here, but Mach 13 has an interesting solution: How to get a variable name as a string in PHP

Answer 5

You could use eval:

function debug($variablename)
{
  echo ($variablename . ":<br/>");
  eval("global $". $variablename . ";");
  eval("var_dump($" . $variablename . ");");
}

Usage: debug("myvar") not debug($myvar)

Answer 6

I believe Alix and nickf are suggesting this:

function debug($variablename)
{
  echo ($variablename . ":<br/>");
  global $$variablename; // enable scope
  var_dump($$variablename);
}

I have tested it and it seems to work just as well as Wagger's code (Thanks Wagger: I have tried so many times to write this and the global variable declaration was my stumbling block)