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run code in 200+ php & hhvm versions
Bugs & Features
<?php $a = ''; $a[3] = 4; // PHP 7.0 and older : var_dump($a); // PHP 7.1 and more recent ?>
based on OWlZp
Output for 7.1.0 - 7.3.1
string(4) " 4"
Output for 4.3.0 - 5.6.38, hhvm-3.10.1 - 3.22.0, 7.0.0 - 7.0.33
array(1) { [3]=> int(4) }