Mutable Collection

Mutable_Collection is a basic implementation of Collection. Unlike an immutable collection, items can always be added, to this collection, but it cannot be directly removed from the collection instance.

If you want to remove an item from the collection, use Mutable_Collection_With_Remove, instead.

Alternatively, you can filter the item using a query, but this does not mutate the original collection, it creates a new one:

use \Underpin\Registries\Immutable_Collection;
use \Underpin\Interfaces\Identifiable_Int;
class Blog_Post implements Identifiable_Int {
  public function __construct(protected int $id){
  
  }
  
  public function get_id() : ?int{
    return $this->id;
  }
}

$collection = Immutable_Collection::make(Blog_Post::class)->seed([
  new Blog_Post(1),
  new Blog_Post(2),
  new Blog_Post(3),
  new Blog_Post(4),
  new Blog_Post(5),
]);

// Get a registry that does not include the item with the ID of 3
$filtered = $collection->query()->key_not_in(3)->get_results();