pub fn merge(
parsed_elements: impl Iterator<Item = Result<ParsedElement>>,
parsed_interfaces: impl Iterator<Item = Result<ParsedInterface>>,
parsed_aria_elements: impl Iterator<Item = Result<ParsedAriaElement>>,
parsed_aria_roles: impl Iterator<Item = Result<ParsedAriaRole>>,
parsed_aria_properties: impl Iterator<Item = Result<ParsedAriaProperty>>,
) -> Result<Vec<MergedElement>>