15     state: PermutationState,
26 enum PermutationState {  enum
67         let state = PermutationState::Complete(CompleteState::Start { n: 0, k: 0 });  in permutations()
85         PermutationState::StartUnknownLen { k }  in permutations()
87         PermutationState::Empty  in permutations()
109             PermutationState::StartUnknownLen { .. } => panic!("unexpected iterator state"),  in next()
110             PermutationState::OngoingUnknownLen { k, min_n } => {  in next()
116             PermutationState::Complete(CompleteState::Start { .. }) => None,  in next()
117             PermutationState::Complete(CompleteState::Ongoing { ref indices, ref cycles }) => {  in next()
122             PermutationState::Empty => None  in next()
139             PermutationState::StartUnknownLen { k } => {  in count()
145             PermutationState::OngoingUnknownLen { k, min_n } => {  in count()
152             PermutationState::Complete(state) => from_complete(state),  in count()
153             PermutationState::Empty => 0  in count()
159             PermutationState::StartUnknownLen { .. } |  in size_hint()
160 …  PermutationState::OngoingUnknownLen { .. } => (0, None), // TODO can we improve this lower bound?  in size_hint()
161             PermutationState::Complete(ref state) => match state.remaining() {  in size_hint()
165             PermutationState::Empty => (0, Some(0))  in size_hint()
179             PermutationState::StartUnknownLen { k } => {  in advance()
180                 PermutationState::OngoingUnknownLen { k, min_n: k }  in advance()
182             PermutationState::OngoingUnknownLen { k, min_n } => {  in advance()
184                     PermutationState::OngoingUnknownLen { k, min_n: min_n + 1 }  in advance()
195                     PermutationState::Complete(complete_state)  in advance()
198             PermutationState::Complete(ref mut state) => {  in advance()
203             PermutationState::Empty => { return; }  in advance()