pub fn ancestors<'tcx>(
    tcx: TyCtxt<'tcx>,
    trait_def_id: DefId,
    start_from_impl: DefId
) -> Result<Ancestors<'tcx>, ErrorGuaranteed>
Expand description

Walk up the specialization ancestors of a given impl, starting with that impl itself.

Returns Err if an error was reported while building the specialization graph.