Return first key of associative array in PHP

Question

I\'m trying to obtain the first key of an associative array, without creating a temporary variable via array_keys() or the like, to pass by reference. Unfortuna

Answer 1

What about using array_slice (in combination with array_keys for associative arrays)?

$a = range(0,999999);
var_dump(memory_get_peak_usage());
$k = array_keys(array_slice($a, 0, 1, TRUE))[0];
var_dump(memory_get_peak_usage());
var_dump($k);
$k = array_keys($a)[0];
var_dump(memory_get_peak_usage());

Gives as output (at least with me):

int(36354360)
int(36355112)
int(0)
int(72006024)
int(0)