- var_dump: documentation ( source)
<?php
$zero = 0; // global scope
$f1 = function() use ($zero) {
$one = 1; // third-level closure scope of f4
echo $one;
$f2 = function() use ($zero, $one) {
$two = 2; // second-level closure scope of f4
echo $one;
$f3 = function() use ($zero, $one, $two) {
$three = 3; // first-level closure scope of f4
$f4 = function() use ($zero, $one, $two, $three) {
$four = 4; // local scope of f4
var_dump($zero + $one + $two + $three + $four);
};
$f4();
};
};
};
$f1();
$f2();