3v4l.org

run code in 300+ PHP versions simultaneously
<?php $v = '<html'; echo "XXX v is"; echo "len ".strlen($v)."\n"; echo substr($v,1)."\n "; echo ord($v[0])."\n "; echo $v."\n "; flush(); echo "echoing done\n"; echo "vd1\n"; echo "vd2\n"; var_dump($v); echo "AFTER\n";

preferences:
41.02 ms | 402 KiB | 5 Q