Fatal error: Uncaught TypeError: array_reduce(): Argument #2 ($callback) must be a valid callback, function "sum" not found or invalid function name in /in/skIK5:10
Stack trace:
#0 /in/skIK5(10): array_reduce(Array, 'sum')
#1 {main}
thrown in /in/skIK5 on line 10
Process exited with code 255.
Warning: array_reduce(): The second argument, 'sum', should be a valid callback in /in/skIK5 on line 10
NULL
Output for 4.3.0 - 4.3.1
Warning: array_reduce() [http://www.php.net/function.array-reduce]: The second argument, 'sum', should be a valid callback in /in/skIK5 on line 10
NULL