3v4l.org

run code in 300+ PHP versions simultaneously
<?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();

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40.86 ms | 402 KiB | 5 Q