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<?php $a = ['a'=>1,'b'=>2,'c'=>3]; var_dump(array_reduce($a, function($result, $item){ $key = key($result) == 'a' ? 'a' : 'aa'; $result[$key] = $item; return $result; }));
Output for 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Fatal error: Uncaught TypeError: key(): Argument #1 ($array) must be of type array, null given in /in/rN3WP:5 Stack trace: #0 /in/rN3WP(5): key(NULL) #1 [internal function]: {closure}(NULL, 1) #2 /in/rN3WP(4): array_reduce(Array, Object(Closure)) #3 {main} thrown in /in/rN3WP on line 5
Process exited with code 255.
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28
Fatal error: Uncaught TypeError: key(): Argument #1 ($array) must be of type array, null given in /in/rN3WP:5 Stack trace: #0 /in/rN3WP(5): key(NULL) #1 [internal function]: {closure}(NULL, 1) #2 /in/rN3WP(8): array_reduce(Array, Object(Closure)) #3 {main} thrown in /in/rN3WP on line 5
Process exited with code 255.
Output for 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, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33
Warning: key() expects parameter 1 to be array, null given in /in/rN3WP on line 5 array(1) { ["aa"]=> int(3) }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/rN3WP on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/rN3WP on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/rN3WP on line 3
Process exited with code 255.
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206.89 ms | 401 KiB | 314 Q