message: element_vec - into_option_element
diff: @@ -178,7 +178,9 @@ macro_rules! element_vec {
  {
  let mut elements = Vec::new();
  $(
  - elements.push($element.into_raw_element());
  + if let Some(element) = $element.into_option_element() {
  + elements.push(element.into_raw_element());
  + }
  )*
  elements
  }
  