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<?php // the unroll: $arr = array(1 => 'one', 2 => 'two', 3 => 'three'); $a = &$arr[1]; var_dump($a,$arr); $a = &$arr[2]; var_dump($a,$arr); $a = &$arr[3]; var_dump($a,$arr);
Output for 5.2.1 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
string(3) "one" array(3) { [1]=> &string(3) "one" [2]=> string(3) "two" [3]=> string(5) "three" } string(3) "two" array(3) { [1]=> string(3) "one" [2]=> &string(3) "two" [3]=> string(5) "three" } string(5) "three" array(3) { [1]=> string(3) "one" [2]=> string(3) "two" [3]=> &string(5) "three" }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0
string(3) "one" array(3) { [1]=> &string(3) "one" [2]=> string(3) "two" [3]=> string(5) "three" } string(3) "two" array(3) { [1]=> &string(3) "one" [2]=> &string(3) "two" [3]=> string(5) "three" } string(5) "three" array(3) { [1]=> &string(3) "one" [2]=> &string(3) "two" [3]=> &string(5) "three" }

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