Function rustc::ty::wf::obligations [−] [src]

pub fn obligations<'a, 'gcx, 'tcx>(infcx: &InferCtxt<'a, 'gcx, 'tcx>, body_id: NodeId, ty: Ty<'tcx>, span: Span) -> Option<Vec<PredicateObligation<'tcx>>>

Unstable (rustc_private)

Returns the set of obligations needed to make ty well-formed. If ty contains unresolved inference variables, this may include further WF obligations. However, if ty IS an unresolved inference variable, returns None, because we are not able to make any progress at all. This is to prevent "livelock" where we say "$0 is WF if $0 is WF".