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<?php $a = 'foo'; $b = & $a; $c = 'moo'; $vars = get_defined_vars(); $vars['a'] = 'OMG'; $vars['c'] = 'Pie'; var_dump($a, $b, $c, debug_zval_dump($a), debug_zval_dump($b), debug_zval_dump($c));

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30.67 ms | 402 KiB | 5 Q