3v4l.org

run code in 300+ PHP versions simultaneously
<?php $o1 = array('foo' => '1', 'bar' => '2'); $o2 = array('foo' => '3', 'baz' => '4'); $o3 = array_intersect_key($o2, array_fill_keys(array('foo'), null)); print_r($o1 + $o3);

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