Differences in how array_merge and how "+" handles conflicting indexes.

DiffTest-array_merge.php

<?php
$arr1 = array(
	'a' => 'Hello',
	'b' => 'World',
	'c' => 'Foo',
	'd' => 'Bar'
);
$arr2 = array(
	'a' => 'Fello',
	'b' => 'Borld',
	'c' => 'Hoo',
	'd' => 'War'
);
$arr3 = array(
	0 => 1,
	1 => 2,
	2 => 3,
	3 => 4
);
$arr4 = array(
	0 => 5,
	1 => 6,
	2 => 7,
	3 => 8
);

echo "1: ";
var_dump(array_merge($arr1, $arr2, $arr3, $arr4));

echo "\n\n";

echo "2: ";
var_dump($arr1 + $arr2 + $arr3 + $arr4);

echo "\n\n";