Online PHP editor | output for cDdjV

Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6: array(2) { [0]=> string(3) "foo" [2]=> int(-1) } Fatal error: Uncaught TypeError: array_filter(): Argument #2 ($callback) must be a valid callback or null, function "isset" not found or invalid function name in /in/cDdjV:12 Stack trace: #0 /in/cDdjV(12): array_filter(Array, 'isset') #1 {main} thrown in /in/cDdjV on line 12
Process exited with code 255.
Output for 8.3.5: Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 array(2) { [0]=> string(3) "foo" [2]=> int(-1) } Fatal error: Uncaught TypeError: array_filter(): Argument #2 ($callback) must be a valid callback or null, function "isset" not found or invalid function name in /in/cDdjV:12 Stack trace: #0 /in/cDdjV(12): array_filter(Array, 'isset') #1 {main} thrown in /in/cDdjV on line 12
Process exited with code 255.
Output for 8.0.0 - 8.0.30: array(2) { [0]=> string(3) "foo" [2]=> int(-1) } Fatal error: Uncaught TypeError: array_filter(): Argument #2 ($callback) must be a valid callback, function "isset" not found or invalid function name in /in/cDdjV:12 Stack trace: #0 /in/cDdjV(12): array_filter(Array, 'isset') #1 {main} thrown in /in/cDdjV on line 12
Process exited with code 255.
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 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: array(2) { [0]=> string(3) "foo" [2]=> int(-1) } Warning: array_filter() expects parameter 2 to be a valid callback, function 'isset' not found or invalid function name in /in/cDdjV on line 12 NULL
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17: array(2) { [0]=> string(3) "foo" [2]=> int(-1) } Warning: array_filter(): The second argument, 'isset', should be a valid callback in /in/cDdjV on line 12 NULL
Output for 4.3.0 - 4.3.1: array(2) { [0]=> string(3) "foo" [2]=> int(-1) } Warning: array_filter() [http://www.php.net/function.array-filter]: The second argument, 'isset', should be a valid callback in /in/cDdjV on line 12 NULL