pub enum Entry<'a, K, V, const N: usize, S> {
Occupied(OccupiedEntry<'a, K, V, N, S>),
Vacant(VacantEntry<'a, K, V, N, S>),
}
Expand description
Variants§
Occupied(OccupiedEntry<'a, K, V, N, S>)
An occupied entry.
Vacant(VacantEntry<'a, K, V, N, S>)
A vacant entry.
Implementations§
source§impl<'a, K, V, const N: usize, S> Entry<'a, K, V, N, S>
impl<'a, K, V, const N: usize, S> Entry<'a, K, V, N, S>
sourcepub fn or_insert(self, default: V) -> &'a mut Vwhere
K: Hash,
S: BuildHasher,
pub fn or_insert(self, default: V) -> &'a mut Vwhere
K: Hash,
S: BuildHasher,
Ensures a value is in the entry by inserting the default if empty, and returns a mutable reference to the value in the entry.
§Examples
use halfbrown::HashMap;
let mut map: HashMap<&str, u32> = HashMap::new();
map.entry("poneyland").or_insert(3);
assert_eq!(map["poneyland"], 3);
*map.entry("poneyland").or_insert(10) *= 2;
assert_eq!(map["poneyland"], 6);
sourcepub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut Vwhere
K: Hash,
S: BuildHasher,
pub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut Vwhere
K: Hash,
S: BuildHasher,
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.
§Examples
use halfbrown::HashMap;
let mut map: HashMap<&str, String> = HashMap::new();
let s = "hoho".to_string();
map.entry("poneyland").or_insert_with(|| s);
assert_eq!(map["poneyland"], "hoho".to_string());
sourcepub fn key(&self) -> &K
pub fn key(&self) -> &K
Returns a reference to this entry’s key.
§Examples
use halfbrown::HashMap;
let mut map: HashMap<&str, u32> = HashMap::new();
assert_eq!(map.entry("poneyland").key(), &"poneyland");
sourcepub fn and_modify<F>(self, f: F) -> Self
pub fn and_modify<F>(self, f: F) -> Self
Provides in-place mutable access to an occupied entry before any potential inserts into the map.
§Examples
use halfbrown::HashMap;
let mut map: HashMap<&str, u32> = HashMap::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);
source§impl<'a, K, V: Default, const N: usize, S> Entry<'a, K, V, N, S>
impl<'a, K, V: Default, const N: usize, S> Entry<'a, K, V, N, S>
sourcepub fn or_default(self) -> &'a mut Vwhere
K: Hash,
S: BuildHasher,
pub fn or_default(self) -> &'a mut Vwhere
K: Hash,
S: BuildHasher,
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.
§Examples
use halfbrown::HashMap;
let mut map: HashMap<&str, Option<u32>> = HashMap::new();
map.entry("poneyland").or_default();
assert_eq!(map["poneyland"], None);
Trait Implementations§
Auto Trait Implementations§
impl<'a, K, V, const N: usize, S> RefUnwindSafe for Entry<'a, K, V, N, S>
impl<'a, K, V, const N: usize, S> Send for Entry<'a, K, V, N, S>
impl<'a, K, V, const N: usize, S> Sync for Entry<'a, K, V, N, S>
impl<'a, K, V, const N: usize, S> Unpin for Entry<'a, K, V, N, S>where
K: Unpin,
impl<'a, K, V, const N: usize, S> !UnwindSafe for Entry<'a, K, V, N, S>
Blanket Implementations§
source§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
Mutably borrows from an owned value. Read more