Struct VacantEntry

pub struct VacantEntry<'a, K, V> { /* private fields */ }

A view into a vacant entry in an IndexMap. It is part of the Entry enum.

Implementations

impl<'a, K, V> VacantEntry<'a, K, V>

pub fn index(&self) -> usize

Return the index where a key-value pair may be inserted.

pub fn key(&self) -> &K

Gets a reference to the key that was used to find the entry.

pub fn into_key(self) -> K

Takes ownership of the key, leaving the entry vacant.

pub fn insert(self, value: V) -> &'a mut V

Inserts the entry’s key and the given value into the map, and returns a mutable reference to the value.

Computes in O(1) time (amortized average).

pub fn insert_entry(self, value: V) -> OccupiedEntry<'a, K, V>

Inserts the entry’s key and the given value into the map, and returns an OccupiedEntry.

Computes in O(1) time (amortized average).

pub fn insert_sorted(self, value: V) -> (usize, &'a mut V)

where K: Ord,

Inserts the entry’s key and the given value into the map at its ordered position among sorted keys, and returns the new index and a mutable reference to the value.

If the existing keys are not already sorted, then the insertion index is unspecified (like slice::binary_search), but the key-value pair is inserted at that position regardless.

Computes in O(n) time (average).

pub fn shift_insert(self, index: usize, value: V) -> &'a mut V

Inserts the entry’s key and the given value into the map at the given index, shifting others to the right, and returns a mutable reference to the value.

Panics if index is out of bounds.

Computes in O(n) time (average).

Trait Implementations

impl<K: Debug, V> Debug for VacantEntry<'_, K, V>

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

Formats the value using the given formatter.

impl<K, V> MutableEntryKey for VacantEntry<'_, K, V>

Opt-in mutable access to VacantEntry keys.

See MutableEntryKey for more information.

type Key = K

fn key_mut(&mut self) -> &mut Self::Key

Gets a mutable reference to the entry’s key, either within the map if occupied, or else the new key that was used to find the entry.