collections::btree_map::OccupiedEntry

Struct collections::btree_map::OccupiedEntry

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

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

Methods

impl<'a, K: Ord, V> OccupiedEntry<'a, K, V> [src]

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");

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"]);

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);
}

Gets a mutable 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);

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

Converts the entry into a mutable reference to its 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);

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

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);

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"]);

Trait Implementations

impl<'a, K: 'a + Debug + Ord, V: 'a + Debug> Debug for OccupiedEntry<'a, K, V>
1.12.0
[src]

Formats the value using the given formatter.

© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/collections/btree_map/struct.OccupiedEntry.html

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