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<?php $f = function($s) { return $s*2; } ($f)(4);
Output for 5.4.20
Parse error: syntax error, unexpected '(' in /in/2rHHB on line 5
Process exited with code 255.
Output for 5.3.0 - 5.3.27, 5.4.0 - 5.4.19
Parse error: syntax error, unexpected '(' in /in/8nCIP on line 5
Process exited with code 255.

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