Enum std::collections::btree_map::Entry 1.0.0
[−]
[src]
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
.
Variants
Vacant(VacantEntry<'a, K, V>)
A vacant Entry
Occupied(OccupiedEntry<'a, K, V>)
An occupied Entry
Methods
impl<'a, K, V> Entry<'a, K, V> where K: Ord
[src]
fn or_insert(self, default: V) -> &'a mut V
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 std::collections::BTreeMap; let mut map: BTreeMap<&str, usize> = BTreeMap::new(); map.entry("poneyland").or_insert(12); assert_eq!(map["poneyland"], 12);
fn or_insert_with<F>(self, default: F) -> &'a mut V where F: FnOnce() -> V
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 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());
fn key(&self) -> &K
1.10.0
Returns a reference to this entry's key.
Examples
use std::collections::BTreeMap; let mut map: BTreeMap<&str, usize> = BTreeMap::new(); assert_eq!(map.entry("poneyland").key(), &"poneyland");
Trait Implementations
impl<'a, K, V> Debug for Entry<'a, K, V> where K: 'a + Ord + Debug,
V: 'a + Debug
1.12.0[src]
V: 'a + Debug