debug( $myvar, 'myvar' );

debug( $myvar ); // quicker and easier :)

function varName($theVar) {
   $variableName = key($theVar);
   $variableValue = $theVar[$variableName];
   echo ('The name of the variable used in the function call was '.$variableName.'<br />');
   echo ('The value of the variable used in the function call was '.$variableValue.'<br />');
}
$myVar = 'abc';
varName(compact('myVar'));

function vlog() {
    $args = func_get_args();
    foreach ($args as $arg) {
        global ${$arg};
    }
    return json_encode(compact($args));
}

$foo = 'Elvis';
$bar = 42;
$obj = new SomeFancyObject();

log('Something went wrong! vars='.vlog('foo', 'bar', 'obj'));

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

function ev($variable){
    foreach($GLOBALS as $key => $value){
        if($variable===$value){
            echo '<p>$'.$key.' - '.$value.'</p>';
        }
    }
}

$lol = 123;

ev($lol); // $lol - 123

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

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

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

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

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