Enum Entry 

pub enum Entry<'a, K, V, P, H>
where
    P: ExpirePolicy,
{
    Occupied(OccupiedEntry<'a, K, V, P, H>),
    Vacant(VacantEntry<'a, K, V, P, H>),
}

A view into a single entry in a HashMap, which may either be vacant or occupied.

This enum is constructed from the entry method on HashMap.

Variants

Occupied(OccupiedEntry<'a, K, V, P, H>)

Vacant(VacantEntry<'a, K, V, P, H>)

Implementations

impl<'a, K, V, P, H> Entry<'a, K, V, P, H>

where K: Eq + Hash, P: ExpirePolicy, H: BuildHasher,

pub fn insert(self, value: V, init: P::Info) -> OccupiedEntry<'a, K, V, P, H>

Sets the value of the entry, and returns an OccupiedEntry.

Example

use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::time::Duration;

let mut cache = HashMap::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

let entry = cache.entry(0).insert("a", ());
assert_eq!(entry.key(), &0);
assert_eq!(entry.get(), &"a");

assert_eq!(cache.get(&0), Some(&"a"));

pub fn or_insert(self, default: V, init: P::Info) -> &'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.

Example

use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::thread::sleep;
use std::time::Duration;

let mut cache = HashMap::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

cache.entry(0).or_insert(0, ());
assert_eq!(cache.get(&0), Some(&0));

*cache.entry(0).or_insert(200, ()) += 10;
assert_eq!(cache.get(&0), Some(&10));

sleep(Duration::from_millis(10));

cache.entry(0).or_insert(100, ());
assert_eq!(cache.get(&0), Some(&100));

pub fn or_insert_with<F: FnOnce() -> V>( self, default: F, init: P::Info, ) -> &'a mut 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.

Example

use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::thread::sleep;
use std::time::Duration;

let mut cache = HashMap::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

cache.entry("a").or_insert_with(|| "A".to_string(), ());
assert_eq!(cache.get(&"a"), Some(&"A".to_string()));

cache
    .entry("a")
    .or_insert_with(|| "B".to_string(), ())
    .push('B');
assert_eq!(cache.get(&"a"), Some(&"AB".to_string()));

sleep(Duration::from_millis(10));

cache.entry("a").or_insert_with(|| "C".to_string(), ());
assert_eq!(cache.get(&"a"), Some(&"C".to_string()));

pub fn or_insert_with_key<F: FnOnce(&K) -> V>( self, default: F, init: P::Info, ) -> &'a mut V

Ensures a value is in the entry by inserting, if empty, the result of the default function. This method allows for generating key-derived values for insertion by providing the default function a reference to the key that was moved during the .entry(key) method call.

The reference to the moved key is provided so that cloning or copying the key is unnecessary, unlike with .or_insert_with(|| … ).

Example

use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::time::Duration;

let mut cache = HashMap::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

cache
    .entry("endorphin")
    .or_insert_with_key(|k| k.chars().count(), ());

assert_eq!(cache.get(&"endorphin"), Some(&9));

pub fn key(&self) -> &K

Returns a reference to this entry’s key.

Example

use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::time::Duration;

let mut cache =
    HashMap::<&str, u32, _>::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

assert_eq!(cache.entry("library").key(), &"library");

pub fn and_modify<F>(self, f: F) -> Self

where F: FnOnce(&mut V),

Provides in-place mutable access to an occupied entry before any potential inserts into the HashMap.

Example

use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::time::Duration;

let mut cache = HashMap::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

cache
    .entry("endorphin")
    .and_modify(|v| unreachable!())
    .or_insert(0, ());
assert_eq!(cache.get(&"endorphin"), Some(&0));

cache
    .entry("endorphin")
    .and_modify(|v| *v += 10)
    .or_insert(123, ());
assert_eq!(cache.get(&"endorphin"), Some(&10));

pub fn and_replace_entry_with<F>(self, f: F) -> Self

where F: FnOnce(&K, V) -> Option<V>,

Provides shared access to the key and owned access to the value of an occupied entry and allows to replace or remove it based on the value of the returned option.

Example

use endorphin::map::Entry;
use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::time::Duration;

let mut cache = HashMap::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

match cache
    .entry(10)
    .and_replace_entry_with(|_k, _v| unreachable!())
{
    Entry::Occupied(_) => unreachable!(),
    Entry::Vacant(entry) => assert_eq!(entry.key(), &10),
}

cache.insert(10, 200, ());

match cache.entry(10).and_replace_entry_with(|k, v| Some(k + v)) {
    Entry::Occupied(entry) => assert_eq!(entry.get(), &210),
    Entry::Vacant(_) => unreachable!(),
}

impl<'a, K, V, P, H> Entry<'a, K, V, P, H>

where K: Eq + Hash, V: Default, P: ExpirePolicy, H: BuildHasher,

pub fn or_default(self, init: P::Info) -> &'a mut V

where V: Default,

Ensures a value is in the entry by inserting the default value if empty, and returns a mutable reference to the value in the entry.

Example

use endorphin::policy::LazyFixedTTLPolicy;
use endorphin::HashMap;

use std::time::Duration;

let mut cache = HashMap::<_, u32, _>::new(LazyFixedTTLPolicy::new(Duration::from_millis(10)));

cache.entry("endorphin").or_default(());

assert_eq!(cache.get(&"endorphin"), Some(&u32::default()));