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

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, S>)

🔬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.

Implementations§

🔬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
🔬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
🔬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§

Formats the value using the given formatter. Read more

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.