Struct std::collections::hash_map::VacantEntry1.0.0[][src]

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

A view into a vacant entry in a HashMap. It is part of the Entry enum.

Methods

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

Important traits for &'a mut I

Gets a reference to the key that would be used when inserting a value through the VacantEntry.

Examples

use std::collections::HashMap;

let mut map: HashMap<&str, u32> = HashMap::new();
assert_eq!(map.entry("poneyland").key(), &"poneyland");Run

Take ownership of the key.

Examples

use std::collections::HashMap;
use std::collections::hash_map::Entry;

let mut map: HashMap<&str, u32> = HashMap::new();

if let Entry::Vacant(v) = map.entry("poneyland") {
    v.into_key();
}Run

Important traits for &'a mut I

Sets the value of the entry with the VacantEntry's key, and returns a mutable reference to it.

Examples

use std::collections::HashMap;
use std::collections::hash_map::Entry;

let mut map: HashMap<&str, u32> = HashMap::new();

if let Entry::Vacant(o) = map.entry("poneyland") {
    o.insert(37);
}
assert_eq!(map["poneyland"], 37);Run

Trait Implementations

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

Formats the value using the given formatter. Read more

Auto Trait Implementations

impl<'a, K, V> !Send for VacantEntry<'a, K, V>

impl<'a, K, V> !Sync for VacantEntry<'a, K, V>