3v4l.org

run code in 300+ PHP versions simultaneously
<?php spl_autoload_register(function($c) {var_dump("loading $c");}); defined("JsonIncrementalParser::JSON_PARSER_SUCCESS");
Output for 8.1.0 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
string(29) "loading JsonIncrementalParser"
preferences:
54.86 ms | 406 KiB | 5 Q