[][src]Enum std::collections::hash_map::RawEntryMut

pub enum RawEntryMut<'a, K: 'a, V: 'a, S: 'a> {
    Occupied(RawOccupiedEntryMut<'a, K, V>),
    Vacant(RawVacantEntryMut<'a, K, V, S>),
}
🔬 This is a nightly-only experimental API. (hash_raw_entry #56167)

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

This is a lower-level version of Entry.

This enum is constructed through the raw_entry_mut method on HashMap, then calling one of the methods of that RawEntryBuilderMut.

Variants

Occupied(RawOccupiedEntryMut<'a, K, V>)
🔬 This is a nightly-only experimental API. (hash_raw_entry #56167)

An occupied entry.

Vacant(RawVacantEntryMut<'a, K, V, S>)
🔬 This is a nightly-only experimental API. (hash_raw_entry #56167)

A vacant entry.

Methods

impl<'a, K, V, S> RawEntryMut<'a, K, V, S>[src]

pub fn or_insert(self, default_key: K, default_val: V) -> (&'a mut K, &'a mut V) where
    K: Hash,
    S: BuildHasher
[src]

🔬 This is a nightly-only experimental API. (hash_raw_entry #56167)

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

Examples

#![feature(hash_raw_entry)]
use std::collections::HashMap;

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

map.raw_entry_mut().from_key("poneyland").or_insert("poneyland", 3);
assert_eq!(map["poneyland"], 3);

*map.raw_entry_mut().from_key("poneyland").or_insert("poneyland", 10).1 *= 2;
assert_eq!(map["poneyland"], 6);Run

pub fn or_insert_with<F>(self, default: F) -> (&'a mut K, &'a mut V) where
    F: FnOnce() -> (K, V),
    K: Hash,
    S: BuildHasher
[src]

🔬 This is a nightly-only experimental API. (hash_raw_entry #56167)

Ensures a value is in the entry by inserting the result of the default function if empty, and returns mutable references to the key and value in the entry.

Examples

#![feature(hash_raw_entry)]
use std::collections::HashMap;

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

map.raw_entry_mut().from_key("poneyland").or_insert_with(|| {
    ("poneyland", "hoho".to_string())
});

assert_eq!(map["poneyland"], "hoho".to_string());Run

pub fn and_modify<F>(self, f: F) -> Self where
    F: FnOnce(&mut K, &mut V), 
[src]

🔬 This is a nightly-only experimental API. (hash_raw_entry #56167)

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

Examples

#![feature(hash_raw_entry)]
use std::collections::HashMap;

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

map.raw_entry_mut()
   .from_key("poneyland")
   .and_modify(|_k, v| { *v += 1 })
   .or_insert("poneyland", 42);
assert_eq!(map["poneyland"], 42);

map.raw_entry_mut()
   .from_key("poneyland")
   .and_modify(|_k, v| { *v += 1 })
   .or_insert("poneyland", 0);
assert_eq!(map["poneyland"], 43);Run

Trait Implementations

impl<'_, K: Debug, V: Debug, S> Debug for RawEntryMut<'_, K, V, S>[src]

Auto Trait Implementations

impl<'a, K, V, S> !UnwindSafe for RawEntryMut<'a, K, V, S>

impl<'a, K, V, S> RefUnwindSafe for RawEntryMut<'a, K, V, S> where
    K: RefUnwindSafe,
    S: RefUnwindSafe,
    V: RefUnwindSafe

impl<'a, K, V, S> Unpin for RawEntryMut<'a, K, V, S> where
    K: Unpin,
    V: Unpin

impl<'a, K, V, S> Send for RawEntryMut<'a, K, V, S> where
    K: Send,
    S: Sync,
    V: Send

impl<'a, K, V, S> !Sync for RawEntryMut<'a, K, V, S>

Blanket Implementations

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

impl<T> From<T> for T[src]

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

impl<T> Any for T where
    T: 'static + ?Sized
[src]