Merging arrays with array_push()

array_push.php

<?php

$a = array(
    'one',
    'two',
    'three',
);
$b = array(
    'four',
    'five',
    'six',
);
array_push($a, ...$b);
var_dump($a);

/*
array(6) {
  [0]=>
  string(3) "one"
  [1]=>
  string(3) "two"
  [2]=>
  string(5) "three"
  [3]=>
  string(4) "four"
  [4]=>
  string(4) "five"
  [5]=>
  string(3) "six"
}
*/