Struct hashbrown::hash_set::OccupiedEntry
source · pub struct OccupiedEntry<'a, T, S, A: Allocator = Global> { /* private fields */ }
Expand description
A view into an occupied entry in a HashSet
.
It is part of the Entry
enum.
§Examples
use hashbrown::hash_set::{Entry, HashSet, OccupiedEntry};
let mut set = HashSet::new();
set.extend(["a", "b", "c"]);
let _entry_o: OccupiedEntry<_, _> = set.entry("a").insert();
assert_eq!(set.len(), 3);
// Existing key
match set.entry("a") {
Entry::Vacant(_) => unreachable!(),
Entry::Occupied(view) => {
assert_eq!(view.get(), &"a");
}
}
assert_eq!(set.len(), 3);
// Existing key (take)
match set.entry("c") {
Entry::Vacant(_) => unreachable!(),
Entry::Occupied(view) => {
assert_eq!(view.remove(), "c");
}
}
assert_eq!(set.get(&"c"), None);
assert_eq!(set.len(), 2);
Implementations§
source§impl<T, S, A: Allocator> OccupiedEntry<'_, T, S, A>
impl<T, S, A: Allocator> OccupiedEntry<'_, T, S, A>
sourcepub fn get(&self) -> &T
pub fn get(&self) -> &T
Gets a reference to the value in the entry.
§Examples
use hashbrown::hash_set::{Entry, HashSet};
let mut set: HashSet<&str> = HashSet::new();
set.entry("poneyland").or_insert();
match set.entry("poneyland") {
Entry::Vacant(_) => panic!(),
Entry::Occupied(entry) => assert_eq!(entry.get(), &"poneyland"),
}
sourcepub fn remove(self) -> T
pub fn remove(self) -> T
Takes the value out of the entry, and returns it. Keeps the allocated memory for reuse.
§Examples
use hashbrown::HashSet;
use hashbrown::hash_set::Entry;
let mut set: HashSet<&str> = HashSet::new();
// The set is empty
assert!(set.is_empty() && set.capacity() == 0);
set.entry("poneyland").or_insert();
let capacity_before_remove = set.capacity();
if let Entry::Occupied(o) = set.entry("poneyland") {
assert_eq!(o.remove(), "poneyland");
}
assert_eq!(set.contains("poneyland"), false);
// Now set hold none elements but capacity is equal to the old one
assert!(set.len() == 0 && set.capacity() == capacity_before_remove);
Trait Implementations§
Auto Trait Implementations§
impl<'a, T, S, A> Freeze for OccupiedEntry<'a, T, S, A>
impl<'a, T, S, A> RefUnwindSafe for OccupiedEntry<'a, T, S, A>
impl<'a, T, S, A> Send for OccupiedEntry<'a, T, S, A>
impl<'a, T, S, A> Sync for OccupiedEntry<'a, T, S, A>
impl<'a, T, S, A> Unpin for OccupiedEntry<'a, T, S, A>
impl<'a, T, S, A = Global> !UnwindSafe for OccupiedEntry<'a, T, S, A>
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