pub(crate) fn companion_lifetime_marker(
generics: &Generics,
fields: &mut Vec<(Ident, TokenStream)>,
) -> (TokenStream, TokenStream)Expand description
Keep lifetimes erased by column expansion or skipped fields in the companion. Columns that still borrow already carry their lifetimes; only missing ones need a marker. This adds no data column or element-type trait requirements.