Enum Entry

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

A view into a single entry in a map, which may either be vacant or occupied.

This enum is constructed from the entry method on ArenaMap.

Variants

Vacant(VacantEntry<'a, IDX, V>)

A vacant entry.

Occupied(OccupiedEntry<'a, IDX, V>)

An occupied entry.

Implementations

impl<'a, IDX, V> Entry<'a, IDX, V>

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

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: FnOnce() -> V>(self, default: F) -> &'a mut V

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: FnOnce(&mut V)>(self, f: F) -> Self

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

impl<'a, IDX, V> Entry<'a, IDX, V>

where V: Default,

pub fn or_default(self) -> &'a mut V

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