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<?php $mock = [ 'foo' => null ]; foreach ($mock as &$item) { $item = 'foo'; } unset($item); $mockCopy = $mock; $mockCopy['foo_copy'] = $mock['foo']; $mockCopy['foo'] = 'bar'; var_dump($mock['foo']);
Output for 5.6.38, 7.1.0 - 7.1.23, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
string(3) "foo"
Output for 7.0.0 - 7.0.31
string(3) "bar"

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