What is the difference between using unset() on a variable within a foreach loop and using unset() on a reference to that variable?

When using unset() on a variable within a foreach loop, it only removes the value of the variable within the loop iteration and does not affect the original array. However, when using unset() on a reference to that variable, it removes the value from the original array as well. 

// Using unset() on a variable within a foreach loop
$array = [1, 2, 3, 4, 5];
foreach ($array as $value) {
    unset($value);
}
print_r($array); // Output: [1, 2, 3, 4, 5]

// Using unset() on a reference to that variable
$array = [1, 2, 3, 4, 5];
foreach ($array as &$value) {
    unset($value);
}
print_r($array); // Output: []

Keywords

unset foreach loop reference variable PHP

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