3v4l.org

run code in 300+ PHP versions simultaneously
<?php echo (function ($echo) { // note the extra set of parentheses! return strtoupper($echo); })('Hello world!');
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
HELLO WORLD!
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
Parse error: syntax error, unexpected '(', expecting ',' or ';' in /in/BDPhc on line 5
Process exited with code 255.

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163.67 ms | 401 KiB | 179 Q