pub enum Entry<'a, K, V> where K: 'a, V: 'a, {
Vacant(VacantEntry<'a, K, V>),
Occupied(OccupiedEntry<'a, K, 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 BTreeMap.
Vacant(VacantEntry<'a, K, V>)
A vacant entry.
Occupied(OccupiedEntry<'a, K, V>)
An occupied entry.
impl<'a, K, V> Entry<'a, K, V> where
K: Ord, [src]
pub fn or_insert(self, default: V) -> &'a mut VⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
[src]
Ensures a value is in the entry by inserting the default if empty, and returns a mutable reference to the value in the entry.
use std::collections::BTreeMap;
let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);
assert_eq!(map["poneyland"], 12);pub fn or_insert_with<F>(self, default: F) -> &'a mut VⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
where
F: FnOnce() -> V, [src]
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.
use std::collections::BTreeMap;
let mut map: BTreeMap<&str, String> = BTreeMap::new();
let s = "hoho".to_string();
map.entry("poneyland").or_insert_with(|| s);
assert_eq!(map["poneyland"], "hoho".to_string());pub fn or_insert_with_key<F>(self, default: F) -> &'a mut VⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
where
F: FnOnce(&K) -> V, [src]
Ensures a value is in the entry by inserting, if empty, the result of the default function, which takes the key as its argument, and returns a mutable reference to the value in the entry.
#![feature(or_insert_with_key)]
use std::collections::BTreeMap;
let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert_with_key(|key| key.chars().count());
assert_eq!(map["poneyland"], 9);pub fn key(&self) -> &KⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
[src]1.10.0
Returns a reference to this entry's key.
use std::collections::BTreeMap;
let mut map: BTreeMap<&str, usize> = BTreeMap::new();
assert_eq!(map.entry("poneyland").key(), &"poneyland");pub fn and_modify<F>(self, f: F) -> Entry<'a, K, V> where
F: FnOnce(&mut V), [src]1.26.0
Provides in-place mutable access to an occupied entry before any potential inserts into the map.
use std::collections::BTreeMap;
let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland")
.and_modify(|e| { *e += 1 })
.or_insert(42);
assert_eq!(map["poneyland"], 42);
map.entry("poneyland")
.and_modify(|e| { *e += 1 })
.or_insert(42);
assert_eq!(map["poneyland"], 43);impl<'a, K, V> Entry<'a, K, V> where
K: Ord,
V: Default, [src]
pub fn or_default(self) -> &'a mut VⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
[src]1.28.0
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.
use std::collections::BTreeMap;
let mut map: BTreeMap<&str, Option<usize>> = BTreeMap::new();
map.entry("poneyland").or_default();
assert_eq!(map["poneyland"], None);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> where
K: Send,
V: Send, impl<'a, K, V> Sync for Entry<'a, K, V> where
K: Sync,
V: Sync, impl<'a, K, V> Unpin for Entry<'a, K, V> where
K: Unpin, impl<'a, K, V> !UnwindSafe for Entry<'a, K, V>impl<T> Any for T where
T: 'static + ?Sized, [src]
impl<T> Borrow<T> for T where
T: ?Sized, [src]
fn borrow(&self) -> &TⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
[src]
impl<T> BorrowMut<T> for T where
T: ?Sized, [src]
fn borrow_mut(&mut self) -> &mut TⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized,
type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized,
type Item = <I as Iterator>::Item;
impl<R: Read + ?Sized, '_> Read for &'_ mut R
impl<W: Write + ?Sized, '_> Write for &'_ mut W
[src]
impl<T> From<T> for T[src]
impl<T, U> Into<U> for T where
U: From<T>, [src]
impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]
type Error = InfallibleThe type returned in the event of a conversion error.
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]
impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/collections/btree_map/enum.Entry.html