Trait StoreMutRef 

pub trait StoreMutRef<K, V>: Store<K, V> {
    // Required methods
    fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut V>
       where K: Borrow<Q>,
             Q: Key;
    fn get_or_insert_default(&mut self, key: &K) -> &mut V
       where V: Default;
}

Mutable store that can return mutable references.

This trait extends StoreMut, adding the possibility to obtain mutable references as a requirement, so values can be mutated in-place.

Examples

use std::collections::HashMap;
use zrx_store::{StoreMut, StoreMutRef};

// Create store and initial state
let mut store = HashMap::new();
store.insert("key", 42);

// Obtain mutable reference to value
let value = store.get_mut(&"key");
assert_eq!(value, Some(&mut 42));

Required Methods

fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut V>

where K: Borrow<Q>, Q: Key,

Returns a mutable reference to the value identified by the key.

fn get_or_insert_default(&mut self, key: &K) -> &mut V

where V: Default,

Returns a mutable reference to the value or creates the default.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<K, V> StoreMutRef<K, V> for BTreeMap<K, V>

where K: Key,

fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut V>

where K: Borrow<Q>, Q: Key,

Returns a mutable reference to the value identified by the key.

Examples

use std::collections::BTreeMap;
use zrx_store::{StoreMut, StoreMutRef};

// Create store and initial state
let mut store = BTreeMap::new();
store.insert("key", 42);

// Obtain mutable reference to value
let value = store.get_mut(&"key");
assert_eq!(value, Some(&mut 42));

fn get_or_insert_default(&mut self, key: &K) -> &mut V

where V: Default,

Returns a mutable reference to the value or creates the default.

Examples

use std::collections::BTreeMap;
use zrx_store::StoreMutRef;

// Create store
let mut store = BTreeMap::new();

// Obtain mutable reference to value
let value = store.get_or_insert_default(&"key");
assert_eq!(value, &mut 0);

impl<K, V> StoreMutRef<K, V> for Slab<(K, V)>

where K: Key,

fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut V>

where K: Borrow<Q>, Q: Key,

Returns a mutable reference to the value identified by the key.

Examples

use slab::Slab;
use zrx_store::{StoreMut, StoreMutRef};

// Create store and initial state
let mut store = Slab::new();
StoreMut::insert(&mut store, "key", 42);

// Obtain mutable reference to value
let mut value = StoreMutRef::get_mut(&mut store, &"key");
assert_eq!(value, Some(&mut 42));

fn get_or_insert_default(&mut self, key: &K) -> &mut V

where V: Default,

Returns a mutable reference to the value or creates the default.

Examples

use slab::Slab;
use zrx_store::StoreMutRef;

// Create store
let mut store = Slab::new();

// Obtain mutable reference to value
let value = StoreMutRef::get_or_insert_default(&mut store, &"key");
assert_eq!(value, &mut 0);

impl<K, V, S> StoreMutRef<K, V> for HashMap<K, V, S>

where K: Key, S: BuildHasher,

fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut V>

where K: Borrow<Q>, Q: Key,

Returns a mutable reference to the value identified by the key.

Examples

use std::collections::HashMap;
use zrx_store::{StoreMut, StoreMutRef};

// Create store and initial state
let mut store = HashMap::new();
store.insert("key", 42);

// Obtain mutable reference to value
let value = store.get_mut(&"key");
assert_eq!(value, Some(&mut 42));

fn get_or_insert_default(&mut self, key: &K) -> &mut V

where V: Default,

Returns a mutable reference to the value or creates the default.

Examples

use std::collections::HashMap;
use zrx_store::StoreMutRef;

// Create store
let mut store = HashMap::new();

// Obtain mutable reference to value
let value = store.get_or_insert_default(&"key");
assert_eq!(value, &mut 0);

Implementors

impl<K, V, S> StoreMutRef<K, V> for Queue<K, V, S>

where K: Key, S: StoreMut<K, Item>,

impl<K, V, S> StoreMutRef<K, V> for Stash<K, V, S>

where K: Key, S: StoreMut<K, usize>,