Struct OccupiedEntry

pub struct OccupiedEntry<'a, K, V, A: Allocator + Clone = Global> { pub(in ::collections::btree::map) handle: Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>, pub(in ::collections::btree::map) dormant_map: DormantMutRef<'a, BTreeMap<K, V, A>>, pub(in ::collections::btree::map) alloc: A, pub(in ::collections::btree::map) _marker: PhantomData<&'a mut (K, V)> }

A view into an occupied entry in a BTreeMap. It is part of the Entry enum.

Fields

handle: Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>
dormant_map: DormantMutRef<'a, BTreeMap<K, V, A>>
alloc: A

The BTreeMap will outlive this IntoIter so we don't care about drop order for alloc.

_marker: PhantomData<&'a mut (K, V)>

Implementations

impl<'a, K: Ord, V, A: Allocator + Clone> OccupiedEntry<'a, K, V, A>

fn key(&self) -> &K

Gets a reference to the key in the entry.

Examples

use std::collections::BTreeMap;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);
assert_eq!(map.entry("poneyland").key(), &"poneyland");

fn into_key(self) -> &'a K

Converts the entry into a reference to its key.

fn remove_entry(self) -> (K, V)

Take ownership of the key and value from the map.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(o) = map.entry("poneyland") {
    // We delete the entry from the map.
    o.remove_entry();
}

// If now try to get the value, it will panic:
// println!("{}", map["poneyland"]);

fn get(&self) -> &V

Gets a reference to the value in the entry.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(o) = map.entry("poneyland") {
    assert_eq!(o.get(), &12);
}

fn get_mut(&mut self) -> &mut V

Gets a mutable reference to the value in the entry.

If you need a reference to the OccupiedEntry that may outlive the destruction of the Entry value, see into_mut.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

assert_eq!(map["poneyland"], 12);
if let Entry::Occupied(mut o) = map.entry("poneyland") {
    *o.get_mut() += 10;
    assert_eq!(*o.get(), 22);

    // We can use the same Entry multiple times.
    *o.get_mut() += 2;
}
assert_eq!(map["poneyland"], 24);

fn into_mut(self) -> &'a mut V

Converts the entry into a mutable reference to its value.

If you need multiple references to the OccupiedEntry, see get_mut.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

assert_eq!(map["poneyland"], 12);
if let Entry::Occupied(o) = map.entry("poneyland") {
    *o.into_mut() += 10;
}
assert_eq!(map["poneyland"], 22);

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

Sets the value of the entry with the OccupiedEntry's key, and returns the entry's old value.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(mut o) = map.entry("poneyland") {
    assert_eq!(o.insert(15), 12);
}
assert_eq!(map["poneyland"], 15);

fn remove(self) -> V

Takes the value of the entry out of the map, and returns it.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(o) = map.entry("poneyland") {
    assert_eq!(o.remove(), 12);
}
// If we try to get "poneyland"'s value, it'll panic:
// println!("{}", map["poneyland"]);

fn remove_kv(self) -> (K, V)

Trait Implementations

impl<K: Debug + Ord, V: Debug, A: Allocator + Clone> Debug for OccupiedEntry<'_, K, V, A>

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

Auto Trait Implementations

impl<'a, K, V, A = Global> !UnwindSafe for OccupiedEntry<'a, K, V, A>

impl<'a, K, V, A> Freeze for OccupiedEntry<'a, K, V, A> where Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>: Freeze, DormantMutRef<'a, BTreeMap<K, V, A>>: Freeze, A: Freeze, PhantomData<&'a mut (K, V)>: Freeze,

impl<'a, K, V, A> RefUnwindSafe for OccupiedEntry<'a, K, V, A> where Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>: RefUnwindSafe, DormantMutRef<'a, BTreeMap<K, V, A>>: RefUnwindSafe, A: RefUnwindSafe, PhantomData<&'a mut (K, V)>: RefUnwindSafe,

impl<'a, K, V, A> Send for OccupiedEntry<'a, K, V, A> where Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>: Send, DormantMutRef<'a, BTreeMap<K, V, A>>: Send, A: Send, PhantomData<&'a mut (K, V)>: Send,

impl<'a, K, V, A> Sync for OccupiedEntry<'a, K, V, A> where Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>: Sync, DormantMutRef<'a, BTreeMap<K, V, A>>: Sync, A: Sync, PhantomData<&'a mut (K, V)>: Sync,

impl<'a, K, V, A> Unpin for OccupiedEntry<'a, K, V, A> where Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>: Unpin, DormantMutRef<'a, BTreeMap<K, V, A>>: Unpin, A: Unpin, PhantomData<&'a mut (K, V)>: Unpin,

impl<'a, K, V, A> UnsafeUnpin for OccupiedEntry<'a, K, V, A> where Handle<NodeRef<Mut<'a>, K, V, LeafOrInternal>, KV>: UnsafeUnpin, DormantMutRef<'a, BTreeMap<K, V, A>>: UnsafeUnpin, A: UnsafeUnpin, PhantomData<&'a mut (K, V)>: UnsafeUnpin,

Blanket Implementations

impl<T> Any for OccupiedEntry<'a, K, V, A> where T: 'static + ?Sized,

fn type_id(&self) -> TypeId

impl<T> Borrow<T> for OccupiedEntry<'a, K, V, A> where T: ?Sized,

fn borrow(&self) -> &T

impl<T> BorrowMut<T> for OccupiedEntry<'a, K, V, A> where T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

impl<T> From<T> for OccupiedEntry<'a, K, V, A>

fn from(t: T) -> T

Returns the argument unchanged.

impl<T> SizeHint for OccupiedEntry<'a, K, V, A> where T: ?Sized,

fn lower_bound(&self) -> usize
fn upper_bound(&self) -> Option<usize>

impl<T> SizedTypeProperties for OccupiedEntry<'a, K, V, A>

impl<T, U> Into<U> for OccupiedEntry<'a, K, V, A> where U: From<T>,

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of [From]<T> for U chooses to do.

impl<T, U> TryFrom<U> for OccupiedEntry<'a, K, V, A> where U: Into<T>,

type Error = Infallible;
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

impl<T, U> TryInto<U> for OccupiedEntry<'a, K, V, A> where U: TryFrom<T>,

type Error = <U as TryFrom<T>>::Error;
fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>