Struct hashbrown::hash_set::VacantEntry
source · pub struct VacantEntry<'a, T, S, A: Allocator = Global> { /* private fields */ }
Expand description
A view into a vacant entry in a HashSet
.
It is part of the Entry
enum.
§Examples
use hashbrown::hash_set::{Entry, HashSet, VacantEntry};
let mut set = HashSet::<&str>::new();
let entry_v: VacantEntry<_, _> = match set.entry("a") {
Entry::Vacant(view) => view,
Entry::Occupied(_) => unreachable!(),
};
entry_v.insert();
assert!(set.contains("a") && set.len() == 1);
// Nonexistent key (insert)
match set.entry("b") {
Entry::Vacant(view) => { view.insert(); },
Entry::Occupied(_) => unreachable!(),
}
assert!(set.contains("b") && set.len() == 2);
Implementations§
source§impl<'a, T, S, A: Allocator> VacantEntry<'a, T, S, A>
impl<'a, T, S, A: Allocator> VacantEntry<'a, T, S, A>
sourcepub fn get(&self) -> &T
pub fn get(&self) -> &T
Gets a reference to the value that would be used when inserting
through the VacantEntry
.
§Examples
use hashbrown::HashSet;
let mut set: HashSet<&str> = HashSet::new();
assert_eq!(set.entry("poneyland").get(), &"poneyland");
sourcepub fn into_value(self) -> T
pub fn into_value(self) -> T
Take ownership of the value.
§Examples
use hashbrown::hash_set::{Entry, HashSet};
let mut set: HashSet<&str> = HashSet::new();
match set.entry("poneyland") {
Entry::Occupied(_) => panic!(),
Entry::Vacant(v) => assert_eq!(v.into_value(), "poneyland"),
}
sourcepub fn insert(self) -> OccupiedEntry<'a, T, S, A>where
T: Hash,
S: BuildHasher,
pub fn insert(self) -> OccupiedEntry<'a, T, S, A>where
T: Hash,
S: BuildHasher,
Sets the value of the entry with the VacantEntry
’s value.
§Examples
use hashbrown::HashSet;
use hashbrown::hash_set::Entry;
let mut set: HashSet<&str> = HashSet::new();
if let Entry::Vacant(o) = set.entry("poneyland") {
o.insert();
}
assert!(set.contains("poneyland"));
Trait Implementations§
Auto Trait Implementations§
impl<'a, T, S, A> Freeze for VacantEntry<'a, T, S, A>where
T: Freeze,
impl<'a, T, S, A> RefUnwindSafe for VacantEntry<'a, T, S, A>
impl<'a, T, S, A> Send for VacantEntry<'a, T, S, A>
impl<'a, T, S, A> Sync for VacantEntry<'a, T, S, A>
impl<'a, T, S, A> Unpin for VacantEntry<'a, T, S, A>where
T: Unpin,
impl<'a, T, S, A = Global> !UnwindSafe for VacantEntry<'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