Struct Cursor 

pub struct Cursor<'a, K>
where
    K: 'a,
{ /* private fields */ }

🔬This is a nightly-only experimental API. (btree_cursors)

Available on crate features http and grpc and protobuf only.

A cursor over a BTreeSet.

A Cursor is like an iterator, except that it can freely seek back-and-forth.

Cursors always point to a gap between two elements in the set, and can operate on the two immediately adjacent elements.

A Cursor is created with the BTreeSet::lower_bound and BTreeSet::upper_bound methods.

Implementations

impl<'a, K> Cursor<'a, K>

pub fn next(&mut self) -> Option<&'a K>

🔬This is a nightly-only experimental API. (btree_cursors)

Available on crate feature rustls and crate feature std and non-no_global_oom_handling only.

Advances the cursor to the next gap, returning the element that it moved over.

If the cursor is already at the end of the set then None is returned and the cursor is not moved.

pub fn prev(&mut self) -> Option<&'a K>

🔬This is a nightly-only experimental API. (btree_cursors)

Available on crate feature rustls and crate feature std and non-no_global_oom_handling only.

Advances the cursor to the previous gap, returning the element that it moved over.

If the cursor is already at the start of the set then None is returned and the cursor is not moved.

pub fn peek_next(&self) -> Option<&'a K>

🔬This is a nightly-only experimental API. (btree_cursors)

Available on crate feature rustls and crate feature std and non-no_global_oom_handling only.

Returns a reference to next element without moving the cursor.

If the cursor is at the end of the set then None is returned

pub fn peek_prev(&self) -> Option<&'a K>

🔬This is a nightly-only experimental API. (btree_cursors)

Available on crate feature rustls and crate feature std and non-no_global_oom_handling only.

Returns a reference to the previous element without moving the cursor.

If the cursor is at the start of the set then None is returned.

Trait Implementations

impl<'a, K> Clone for Cursor<'a, K>

where K: Clone + 'a,

fn clone(&self) -> Cursor<'a, K>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<K> Debug for Cursor<'_, K>

where K: Debug,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.