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<?php class Foo { public function flatten() { $data = func_get_args(); return array_reduce($data, function($c, $a){ return array_merge($c, is_array($a) ?$this->flatten(...$a) : [$a]); }, []) ; } } var_dump((new Foo())->flatten(1)); var_dump((new Foo())->flatten()); var_dump((new Foo())->flatten(1, [2], [3, [4,5]]));
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.6 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(1) { [0]=> int(1) } array(0) { } array(5) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) }
preferences:
158.94 ms | 404 KiB | 201 Q