pub enum Entry<'a, K, V> {
Occupied(OccupiedEntry<'a, K, V>),
Vacant(VacantEntry<'a, K, V>),
}
Expand description
Entry for an existing key-value pair or a vacant location to insert one.
Variants§
Occupied(OccupiedEntry<'a, K, V>)
Existing slot with equivalent key.
Vacant(VacantEntry<'a, K, V>)
Vacant slot (no equivalent key in the map).
Implementations§
source§impl<'a, K, V> Entry<'a, K, V>
impl<'a, K, V> Entry<'a, K, V>
sourcepub fn or_insert(self, default: V) -> &'a mut V
pub fn or_insert(self, default: V) -> &'a mut V
Inserts the given default value in the entry if it is vacant and returns a mutable reference to it. Otherwise a mutable reference to an already existent value is returned.
Computes in O(1) time (amortized average).
sourcepub fn or_insert_with<F>(self, call: F) -> &'a mut Vwhere
F: FnOnce() -> V,
pub fn or_insert_with<F>(self, call: F) -> &'a mut Vwhere
F: FnOnce() -> V,
Inserts the result of the call
function in the entry if it is vacant and returns a mutable
reference to it. Otherwise a mutable reference to an already existent value is returned.
Computes in O(1) time (amortized average).
sourcepub fn or_insert_with_key<F>(self, call: F) -> &'a mut V
pub fn or_insert_with_key<F>(self, call: F) -> &'a mut V
Inserts the result of the call
function with a reference to the entry’s key if it is
vacant, and returns a mutable reference to the new value. Otherwise a mutable reference to
an already existent value is returned.
Computes in O(1) time (amortized average).
sourcepub fn key(&self) -> &K
pub fn key(&self) -> &K
Gets a reference to the entry’s key, either within the map if occupied, or else the new key that was used to find the entry.
sourcepub fn index(&self) -> usize
pub fn index(&self) -> usize
Return the index where the key-value pair exists or will be inserted.
sourcepub fn and_modify<F>(self, f: F) -> Entry<'a, K, V>
pub fn and_modify<F>(self, f: F) -> Entry<'a, K, V>
Modifies the entry if it is occupied.
sourcepub fn or_default(self) -> &'a mut Vwhere
V: Default,
pub fn or_default(self) -> &'a mut Vwhere
V: Default,
Inserts a default-constructed value in the entry if it is vacant and returns a mutable reference to it. Otherwise a mutable reference to an already existent value is returned.
Computes in O(1) time (amortized average).
Trait Implementations§
Auto Trait Implementations§
impl<'a, K, V> RefUnwindSafe for Entry<'a, K, V>where
K: RefUnwindSafe,
V: RefUnwindSafe,
impl<'a, K, V> Send for Entry<'a, K, V>
impl<'a, K, V> Sync for Entry<'a, K, V>
impl<'a, K, V> Unpin for Entry<'a, K, V>where
K: Unpin,
impl<'a, K, V> !UnwindSafe for Entry<'a, K, V>
Blanket Implementations§
§impl<U> As for U
impl<U> As for U
§fn as_<T>(self) -> Twhere
T: CastFrom<U>,
fn as_<T>(self) -> Twhere
T: CastFrom<U>,
self
to type T
. The semantics of numeric casting with the as
operator are followed, so <T as As>::as_::<U>
can be used in the same way as T as U
for numeric conversions. Read moresource§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
§impl<T> Downcast for Twhere
T: Any,
impl<T> Downcast for Twhere
T: Any,
§fn into_any(self: Box<T>) -> Box<dyn Any>
fn into_any(self: Box<T>) -> Box<dyn Any>
Box<dyn Trait>
(where Trait: Downcast
) to Box<dyn Any>
. Box<dyn Any>
can
then be further downcast
into Box<ConcreteType>
where ConcreteType
implements Trait
.§fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>
fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>
Rc<Trait>
(where Trait: Downcast
) to Rc<Any>
. Rc<Any>
can then be
further downcast
into Rc<ConcreteType>
where ConcreteType
implements Trait
.§fn as_any(&self) -> &(dyn Any + 'static)
fn as_any(&self) -> &(dyn Any + 'static)
&Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &Any
’s vtable from &Trait
’s.§fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
&mut Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &mut Any
’s vtable from &mut Trait
’s.