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run code in 300+ PHP versions simultaneously
<?php var_dump(substr_count ('haystack', 'tack', 0, 0));
based on jcDIo
Output for 7.1.5 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.24, 7.4.0 - 7.4.13, 8.0.0
int(0)
Output for 7.1.0
int(1)
Output for 5.6.0 - 5.6.28, 7.0.0 - 7.0.20
Warning: substr_count(): Length should be greater than 0 in /in/3B2Ct on line 3 bool(false)