src/Collection.php
public function extend(Collection $collection)
    {
        foreach ($collection as $entity) {
            $this->append($entity);
        }
        return $this;
    }
public function extend(Collection $collection)
    {
        foreach ($collection as $entity) {
            $this->append($entity);
        }
        return $this;
    }
Extend collection with entities from another one

@param Collection $data
@access public

@return static