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run code in 300+ PHP versions simultaneously
<?php function is_even(int $n): bool { $fn = null; $fn = fn(int $nr, bool $not): bool => $nr === 0 ? !$not : $fn(($nr < 0 ? abs($nr) : $nr) - 1, !$not); return $fn($n, false); } for($i = -5; $i <= 12; $i++) { printf('is %d even? %s.%s', $i, is_even($i) ? 'yes': 'no', "\n"); }
based on UigSP
Output for 8.0.0alpha1 - alpha3
Fatal error: Uncaught Error: Value of type null is not callable in /in/2WBFO:5 Stack trace: #0 /in/2WBFO(7): {closure}(-5, false) #1 /in/2WBFO(11): is_even(-5) #2 {main} thrown in /in/2WBFO on line 5
Process exited with code 255.
Output for 7.4.0 - 7.4.8
Fatal error: Uncaught Error: Function name must be a string in /in/2WBFO:5 Stack trace: #0 /in/2WBFO(7): {closure}(-5, false) #1 /in/2WBFO(11): is_even(-5) #2 {main} thrown in /in/2WBFO on line 5
Process exited with code 255.
Output for 7.3.0 - 7.3.20
Parse error: syntax error, unexpected '$nr' (T_VARIABLE), expecting ')' in /in/2WBFO on line 5
Process exited with code 255.
Output for 7.2.0 - 7.2.32
Parse error: syntax error, unexpected '$nr' (T_VARIABLE), expecting ',' or ')' in /in/2WBFO on line 5
Process exited with code 255.