def each_element(path, elements)
      elements = Array(elements)
      Nokogiri::XML::Reader(::File.open(path, 'rb'), nil, nil, Nokogiri::XML::ParseOptions::NOBLANKS).each do |node|
        next unless node.node_type == Nokogiri::XML::Reader::TYPE_ELEMENT && elements.include?(node.name)
        yield Nokogiri::XML(node.outer_xml).root if block_given?
      end
    end
def each_element(path, elements)
      elements = Array(elements)
      Nokogiri::XML::Reader(::File.open(path, 'rb'), nil, nil, Nokogiri::XML::ParseOptions::NOBLANKS).each do |node|
        next unless node.node_type == Nokogiri::XML::Reader::TYPE_ELEMENT && elements.include?(node.name)
        yield Nokogiri::XML(node.outer_xml).root if block_given?
      end
    end
Yield each element of a given type ('row', 'c', etc.) to caller