Enum Entry

pub enum Entry<'a> {
    Occupied(OccupiedEntry<'a>),
    Vacant(VacantEntry<'a>),
}

Entry for an existing key-value pair or a vacant location to insert one.

Variants

Occupied(OccupiedEntry<'a>)

Existing slot with equivalent key.

Vacant(VacantEntry<'a>)

Vacant slot (no equivalent key in the map).

Implementations

impl<'a> Entry<'a>

pub fn key(&self) -> &Value

Returns a reference to this entry’s key.

pub fn or_insert(self, default: Value) -> &'a mut Value

Ensures a value is in the entry by inserting the default if empty, and returns a mutable reference to the value in the entry.

pub fn or_insert_with<F>(self, default: F) -> &'a mut Value

where F: FnOnce() -> Value,

Ensures a value is in the entry by inserting the result of the default function if empty, and returns a mutable reference to the value in the entry.

pub fn and_modify<F>(self, f: F) -> Self

where F: FnOnce(&mut Value),

Provides in-place mutable access to an occupied entry before any potential inserts into the map.