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run code in 500+ PHP versions simultaneously
<?php for($limit=10,$str=str_repeat(" ",$limit);$limit>=0;--$limit){ $arr=explode(" ",$str,$limit); $combined=implode(" ",$arr); if($combined !== $str){ throw new LogicException("implode() did not restore the original string. limit: {$limit}"); } }
Output for 7.1.25 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3

preferences:
95.36 ms | 1464 KiB | 4 Q