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run code in 300+ PHP versions simultaneously
<?php $var1 = "Hello"; $nbr = "var"; $id = 1; echo ${$nbr.$id};
Output for 5.6.38, 7.0.33, 7.1.0 - 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
Hello
preferences:
126.01 ms | 411 KiB | 6 Q