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run code in 300+ PHP versions simultaneously
<?php $arr1 = [1,2,3]; $arr2 = $arr1; debug_zval_dump('arr2'); key($arr2); debug_zval_dump('arr2'); unset($arr1); unset($arr2); $arr1 = [1,2,3]; $arr2 = $arr1; debug_zval_dump('arr2'); key($arr2); debug_zval_dump('arr2');
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
string(4) "arr2" interned string(4) "arr2" interned string(4) "arr2" interned string(4) "arr2" interned
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0, 7.1.7 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
string(4) "arr2" refcount(1) string(4) "arr2" refcount(1) string(4) "arr2" refcount(1) string(4) "arr2" refcount(1)
Output for 7.1.5 - 7.1.6
string(4) "arr2" refcount(2) string(4) "arr2" refcount(2) string(4) "arr2" refcount(2) string(4) "arr2" refcount(2)
preferences:
158.35 ms | 401 KiB | 243 Q