{"ast_node_type":"function","tokens":[{"end":85,"kind":"keyword","start":0,"text":"fn"}]}
    fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
impl<'tcx> ToTrace<'tcx> for ImplSubject<'tcx> {
        match (a, b) {