Modifying External Variables of Anonymous Functions in PHP
External variables modified inside an anonymous function will not change outside:
<?php
$num = 1;
$func = function() use ($num)
{
$num = 2;
};
$func();
echo $num; // 1
?>
For the changes to apply, the variable must be passed by reference:
<?php
$num = 1;
$func = function() use (&$num)
{
$num = 2;
};
$func();
echo $num; // 2
?>
Fix the code so that it works as intended:
<?php
$num1 = 2;
$num2 = 3;
$func = function() use ($num1, $num2)
{
$num1 = $num1 ** 2;
$num2 = $num2 ** 2;
};
$func();
echo $num1;
echo $num2;
?>
