Returns true if the provided function returns true for all elements of an array, false otherwise.
Use array_filter() and count() to check if $func returns true for all the elements in $items.
代码实现
function all($items, $func)
{
  return count(array_filter($items, $func)) === count($items);
}使用样例
all([2, 3, 4, 5], function ($item) {
  return $item > 1;
}); // true