- var_dump: documentation ( source)
<?php
$arr = null;
echo "Should throw a notice when trying to access an element in a non-array data type \n";
$should_throw_notice = 'foo' === $arr['key'];
echo "\n=======\n\n";
echo "Should NOT throw a notice when setting an element in a non-array data type. PHP should type juggle from `null` to `array`.\n\n";
$arr['key'] = 'foo';
var_dump( $arr );