<?php

$s = "123";
$s1 = "test";
$s2 = "45345some";
$s3 = str_repeat("f", 1);
$s4 = str_repeat("f", 2);

$s &= 22;
var_dump($s);

try {
    $s1 &= 11;
    var_dump($s1);
} catch (\TypeError $e) {
    echo $e->getMessage() . \PHP_EOL;
}

$s2 &= 33;
var_dump($s2);

$s3 &= " ";
var_dump($s3);

$s4 &= "  ";
var_dump($s4);

echo "Done\n";
?>