Struct std::collections::btree_map::OccupiedEntry1.0.0[][src]

pub struct OccupiedEntry<'a, K, V> where
    K: 'a,
    V: 'a, 
{ /* fields omitted */ }
Expand description

A view into an occupied entry in a BTreeMap. It is part of the Entry enum.

Implementations

Gets a reference to the key 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.entry("poneyland").key(), &"poneyland");
Run
pub fn remove_entry(self) -> (K, V)1.12.0[src]

Take ownership of the key and value from the map.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(o) = map.entry("poneyland") {
    // We delete the entry from the map.
    o.remove_entry();
}

// If now try to get the value, it will panic:
// println!("{}", map["poneyland"]);
Run

Gets a reference to the value in the entry.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(o) = map.entry("poneyland") {
    assert_eq!(o.get(), &12);
}
Run

Gets a mutable reference to the value in the entry.

If you need a reference to the OccupiedEntry that may outlive the destruction of the Entry value, see into_mut.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

assert_eq!(map["poneyland"], 12);
if let Entry::Occupied(mut o) = map.entry("poneyland") {
    *o.get_mut() += 10;
    assert_eq!(*o.get(), 22);

    // We can use the same Entry multiple times.
    *o.get_mut() += 2;
}
assert_eq!(map["poneyland"], 24);
Run

Converts the entry into a mutable reference to its value.

If you need multiple references to the OccupiedEntry, see get_mut.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

assert_eq!(map["poneyland"], 12);
if let Entry::Occupied(o) = map.entry("poneyland") {
    *o.into_mut() += 10;
}
assert_eq!(map["poneyland"], 22);
Run

Sets the value of the entry with the OccupiedEntry’s key, and returns the entry’s old value.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(mut o) = map.entry("poneyland") {
    assert_eq!(o.insert(15), 12);
}
assert_eq!(map["poneyland"], 15);
Run

Takes the value of the entry out of the map, and returns it.

Examples

use std::collections::BTreeMap;
use std::collections::btree_map::Entry;

let mut map: BTreeMap<&str, usize> = BTreeMap::new();
map.entry("poneyland").or_insert(12);

if let Entry::Occupied(o) = map.entry("poneyland") {
    assert_eq!(o.remove(), 12);
}
// If we try to get "poneyland"'s value, it'll panic:
// println!("{}", map["poneyland"]);
Run

Trait Implementations

Formats the value using the given formatter. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.