Function list_names 

fn list_names(
    elements: &[Value],
    path: &[String],
    rules: &Rules,
    keyed: &Keyed,
) -> (Vec<String>, Vec<Value>)

A keyed list’s elements at path: their entries in format 1 (their own, or the whole list’s), and the elements as format 2 reads them (its local fields out).