Illuminate\Database\Query\Builder::union PHP Method

    public function union($query, $all = false)
    {
        if ($query instanceof Closure) {
            call_user_func($query, $query = $this->newQuery());
        }
        $this->unions[] = compact('query', 'all');
        $this->addBinding($query->getBindings(), 'union');
        return $this;
    }

 /**
  * Add a union statement to the query.
  *
  * @param \Illuminate\Database\Query\Builder|\Closure $query
  * @param bool $all
  * @return \Illuminate\Database\Query\Builder|static 
  * @static 
  */
 public static function union($query, $all = false)
 {
     return \Illuminate\Database\Query\Builder::union($query, $all);
 }