function ComputedItemListTrait::get

File

core/lib/Drupal/Core/TypedData/ComputedItemListTrait.php, line 69

Class

ComputedItemListTrait

Provides common functionality for computed item lists.

Namespace

Code

public function get($index) {
    if (!is_numeric($index)) {
        throw new \InvalidArgumentException('Unable to get a value with a non-numeric delta in a list.');
    }
    // Unlike the base implementation of
    // \Drupal\Core\TypedData\ListInterface::get(), we do not add an empty item
    // automatically because computed item lists need to behave like
    // non-computed ones. For example, calling isEmpty() on a computed item list
    // should return TRUE when the values were computed and the item list is
    // truly empty.
    // @see \Drupal\Core\TypedData\Plugin\DataType\ItemList::get().
    $this->ensureComputedValue();
    return $this->list[$index] ?? NULL;
}