DashMap

https://docs.rs/dashmap/6.2.1/dashmap/
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DashMap is a fast, concurrent associative array and hash map implementation for Rust designed to...
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### hasher() example: get reference to BuildHasher

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap and obtains a reference to its `BuildHasher` (RandomState) using `hasher()`.

```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let hasher = RandomState::new();
let map: DashMap<i32, i32> = DashMap::new();
let hasher: &RandomState = map.hasher();
```

--------------------------------

### Create a DashMap with with_capacity()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a specified starting capacity and inserts two entries.

```rust
use dashmap::DashMap;

let mappings = DashMap::with_capacity(2);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

--------------------------------

### Create a DashMap with with_capacity_and_hasher()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a specified starting capacity and hasher, then inserts two entries.

```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let mappings = DashMap::with_capacity_and_hasher(2, s);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

--------------------------------

### with_capacity_and_hasher(capacity: usize, hasher: S)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a specified starting capacity and hasher.

```APIDOC
## with_capacity_and_hasher(capacity: usize, hasher: S)

### Description
Creates a new DashMap with a specified starting capacity and hasher.

### Method
with_capacity_and_hasher

### Parameters
- **capacity** (usize) - Required - The initial capacity of the map.
- **hasher** (S) - Required - The hasher to use for hashing keys.

### Request Example
```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let mappings = DashMap::with_capacity_and_hasher(2, s);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

### Response
Returns a new DashMap instance with the specified capacity and hasher.
```

--------------------------------

### Create a DashSet with capacity

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Creates a new DashSet with a specified starting capacity.

```rust
use dashmap::DashSet;

let numbers = DashSet::with_capacity(2);
numbers.insert(2);
numbers.insert(8);
```

--------------------------------

### DashSet::with_capacity

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Creates a new DashSet with a specified starting capacity.

```APIDOC
## with_capacity

### Description
Creates a new DashSet with a specified starting capacity.

### Method
with_capacity

### Parameters
- **capacity** (usize) - Required - The initial capacity of the set.

### Request Example
```rust
use dashmap::DashSet;

let numbers = DashSet::with_capacity(2);
numbers.insert(2);
numbers.insert(8);
```

### Response
#### Success Response
- **Self** - A new DashSet instance with the specified capacity.

#### Response Example
```rust
let numbers = DashSet::with_capacity(2);
```
```

--------------------------------

### DashSet::with_capacity_and_hasher

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Creates a new DashSet with a specified starting capacity and hasher.

```APIDOC
## with_capacity_and_hasher

### Description
Creates a new DashSet with a specified starting capacity and hasher.

### Method
with_capacity_and_hasher

### Parameters
- **capacity** (usize) - Required - The initial capacity of the set.
- **hasher** (S) - Required - The hasher to use for hashing keys.

### Request Example
```rust
use dashmap::DashSet;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let numbers = DashSet::with_capacity_and_hasher(2, s);
numbers.insert(2);
numbers.insert(8);
```

### Response
#### Success Response
- **Self** - A new DashSet instance with the specified capacity and hasher.

#### Response Example
```rust
let s = RandomState::new();
let numbers = DashSet::with_capacity_and_hasher(2, s);
```
```

--------------------------------

### Create a DashSet with capacity and hasher

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Creates a new DashSet with a specified starting capacity and hasher.

```rust
use dashmap::DashSet;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let numbers = DashSet::with_capacity_and_hasher(2, s);
numbers.insert(2);
numbers.insert(8);
```

--------------------------------

### with_capacity(capacity: usize)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a specified starting capacity.

```APIDOC
## with_capacity(capacity: usize)

### Description
Creates a new DashMap with a specified starting capacity.

### Method
with_capacity

### Parameters
- **capacity** (usize) - Required - The initial capacity of the map.

### Request Example
```rust
use dashmap::DashMap;

let mappings = DashMap::with_capacity(2);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

### Response
Returns a new DashMap instance with the specified capacity.
```

--------------------------------

### with_capacity_and_hasher_and_shard_amount(capacity: usize, hasher: S, shard_amount: usize)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a specified starting capacity, hasher, and shard amount.

```APIDOC
## with_capacity_and_hasher_and_shard_amount(capacity: usize, hasher: S, shard_amount: usize)

### Description
Creates a new DashMap with a specified starting capacity, hasher, and shard amount. The shard amount must be greater than 0 and a power of two; otherwise, the function will panic.

### Method
with_capacity_and_hasher_and_shard_amount

### Parameters
- **capacity** (usize) - Required - The initial capacity of the map.
- **hasher** (S) - Required - The hasher to use for hashing keys.
- **shard_amount** (usize) - Required - The number of shards to use. Must be greater than 0 and a power of two.

### Request Example
```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let mappings = DashMap::with_capacity_and_hasher_and_shard_amount(2, s, 32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

### Response
Returns a new DashMap instance with the specified capacity, hasher, and shard amount.
```

--------------------------------

### Example: Using shards() on a ReadOnlyView

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.ReadOnlyView.html

Requires the `raw-api` feature to be enabled. Creates a DashMap, converts it to a read-only view with into_read_only(), and prints the number of shards.

```rust
use dashmap::DashMap;

let map = DashMap::<(), ()>::new().into_read_only();
println!("Amount of shards: {}", map.shards().len());
```

--------------------------------

### Example: iterating over a DashMap

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.Iter.html

Creates a DashMap, inserts a key-value pair, and asserts that iter().count() returns 1.

```rust
use dashmap::DashMap;

let map = DashMap::new();
map.insert("hello", "world");
assert_eq!(map.iter().count(), 1);
```

--------------------------------

### Create a DashMap with with_capacity_and_hasher_and_shard_amount()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a specified starting capacity, hasher, and shard amount. The shard amount must be greater than 0 and a power of two; otherwise the function panics.

```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let mappings = DashMap::with_capacity_and_hasher_and_shard_amount(2, s, 32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

--------------------------------

### DashSet::get

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Get a reference to an entry in the set.

```APIDOC
## get

### Description
Get a reference to an entry in the set.

### Method
get

### Parameters
- **key** (&Q) - Required - The key to look up.

### Request Example
```rust
use dashmap::DashSet;

let youtubers = DashSet::new();
youtubers.insert("Bosnian Bill");
assert_eq!(*youtubers.get("Bosnian Bill").unwrap(), "Bosnian Bill");
```

### Response
#### Success Response
- **Option<Ref<'a, K>>** - A reference to the entry if it exists, `None` otherwise.

#### Response Example
```rust
let youtubers = DashSet::new();
youtubers.insert("Bosnian Bill");
let entry = youtubers.get("Bosnian Bill");
```
```

--------------------------------

### Iter::step_by

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.Iter.html

Creates an iterator starting at the same point, but stepping by the given amount at each iteration. This is a standard iterator adapter.

```APIDOC
## Iter::step_by

### Description
Creates an iterator starting at the same point, but stepping by the given amount at each iteration. This is a standard iterator adapter.

### Method
`fn step_by(self, step: usize) -> StepBy<Self>`

### Parameters
- `self` (consumed) - The iterator instance.
- `step` (usize) - The step size between elements.

### Returns
- `StepBy<Self>` - An iterator that steps by the given amount.

### Example
```rust
use dashmap::DashMap;

let map = DashMap::new();
map.insert("hello", "world");
let iter = map.iter().step_by(1);
assert_eq!(iter.count(), 1);
```
```

--------------------------------

### shards() example: print number of shards

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Requires the `raw-api` feature. Creates a new DashMap and prints the number of shards using `shards().len()`.

```rust
use dashmap::DashMap;

let map = DashMap::<(), ()>::new();
println!("Amount of shards: {}", map.shards().len());
```

--------------------------------

### OwningIter::step_by

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.OwningIter.html

Creates an iterator starting at the same point, but stepping by the given amount at each iteration.

```APIDOC
## OwningIter::step_by

### Description
Creates an iterator starting at the same point, but stepping by the given amount at each iteration.

### Method
`fn step_by(self, step: usize) -> StepBy<Self>`

### Parameters
- `self` (owned) - The iterator instance.
- `step` (usize) - The step size.

### Returns
- `StepBy<Self>` - An iterator that steps by the given amount.
```

--------------------------------

### get

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.ReadOnlyView.html

Returns a reference to the value corresponding to the key.

```APIDOC
## get

### Description
Returns a reference to the value corresponding to the key.

### Method
get

### Signature
`pub fn get<Q>(&'a self, key: &Q) -> Option<&'a V> where K: Borrow<Q>, Q: Hash + Eq + ?Sized`

### Parameters
- `key` (`&Q`) - The key to look up.

### Returns
- `Option<&'a V>` - A reference to the value if found, otherwise `None`.
```

--------------------------------

### insert() example: insert key-value pair

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Inserts a key and value into a DashMap. May deadlock if called while holding any reference into the map.

```rust
use dashmap::DashMap;

let map = DashMap::new();
map.insert("I am the key!", "And I am the value!");
```

--------------------------------

### Get reference from DashSet

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Retrieves a reference to an entry in the set.

```rust
use dashmap::DashSet;

let youtubers = DashSet::new();
youtubers.insert("Bosnian Bill");
assert_eq!(*youtubers.get("Bosnian Bill").unwrap(), "Bosnian Bill");
```

--------------------------------

### determine_map() example: find shard for a key

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Requires the `raw-api` feature. Creates a map, inserts a key, and prints the shard index for that key using `determine_map`.

```rust
use dashmap::DashMap;

let map = DashMap::new();
map.insert("coca-cola", 1.4);
println!("coca-cola is stored in shard: {}", map.determine_map("coca-cola"));
```

--------------------------------

### shards_mut() example: insert into a specific shard

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Requires the `raw-api` feature. Demonstrates using `shards_mut()` to insert a key-value pair into a specific shard, using a custom hasher and `determine_map` to find the shard index.

```rust
use dashmap::DashMap;
use dashmap::SharedValue;
use std::hash::{Hash, Hasher, BuildHasher};

let mut map = DashMap::<i32, &'static str>::new();
let shard_ind = map.determine_map(&42);
let mut factory = map.hasher().clone();
let hasher = |tuple: &(i32, SharedValue<&'static str>)| {
    let mut hasher = factory.build_hasher();
    tuple.0.hash(&mut hasher);
    hasher.finish()
};
let data = (42, SharedValue::new("forty two"));
let hash = hasher(&data);
map.shards_mut()[shard_ind].get_mut().insert(hash, data, hasher);
assert_eq!(*map.get(&42).unwrap(), "forty two");
```

--------------------------------

### determine_shard() example: find shard for a hash

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Requires the `raw-api` feature. Computes a hash for a key using `hash_usize` and prints the shard index for that hash using `determine_shard`.

```rust
use dashmap::DashMap;

let map: DashMap<i32, i32> = DashMap::new();
let key = "key";
let hash = map.hash_usize(&key);
println!("hash is stored in shard: {}", map.determine_shard(hash));
```

--------------------------------

### Collect key-value pairs from DashMap using into_iter

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.OwningIter.html

Example from the documentation showing how to create a DashMap, insert two entries, and collect the key-value pairs into a Vec using into_iter(). The resulting vector has a length of 2.

```rust
use dashmap::DashMap;

let map = DashMap::new();
map.insert("hello", "world");
map.insert("alex", "steve");
let pairs: Vec<(&'static str, &'static str)> = map.into_iter().collect();
assert_eq!(pairs.len(), 2);
```

--------------------------------

### remove() example: remove entry and assert value

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Removes an entry from the map, returning the key and value. May deadlock if called while holding any reference into the map.

```rust
use dashmap::DashMap;

let soccer_team = DashMap::new();
soccer_team.insert("Jack", "Goalie");
assert_eq!(soccer_team.remove("Jack").unwrap().1, "Goalie");
```

--------------------------------

### new

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Creates a new unlocked RwLock instance.

```APIDOC
## new

### Description
Creates a new instance of an `RwLock<T>` which is unlocked.

### Signature
`pub const fn new(val: T) -> RwLock<R, T>`

### Parameters
- `val (T)` - The initial value to store in the lock.

### Returns
A new `RwLock<R, T>` instance.

```

--------------------------------

### get

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Get an immutable reference to an entry in the map. May deadlock if called when holding a mutable reference into the map.

```APIDOC
## get(key)

### Description
Get an immutable reference to an entry in the map.

### Method
get

### Signature
pub fn get<Q>(&'a self, key: &Q) -> Option<Ref<'a, K, V>>
where K: Borrow<Q>, Q: Hash + Eq + ?Sized,

### Parameters
- **key** (&Q) - Required - The key to look up.

### Locking Behaviour
May deadlock if called when holding a mutable reference into the map.

### Example
```rust
use dashmap::DashMap;

let youtubers = DashMap::new();
youtubers.insert("Bosnian Bill", 457000);
assert_eq!(*youtubers.get("Bosnian Bill").unwrap(), 457000);
```
```

--------------------------------

### Get immutable reference with get

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Retrieves an immutable reference to an entry. May deadlock if called while holding a mutable reference.

```rust
use dashmap::DashMap;

let youtubers = DashMap::new();
youtubers.insert("Bosnian Bill", 457000);
assert_eq!(*youtubers.get("Bosnian Bill").unwrap(), 457000);
```

--------------------------------

### Try to get mutable reference with try_get_mut

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Attempts to get a mutable reference without blocking. Returns TryResult::Locked if the shard is currently locked.

```rust
use dashmap::DashMap;
use dashmap::try_result::TryResult;

let map = DashMap::new();
map.insert("Johnny", 21);

*map.try_get_mut("Johnny").unwrap() += 1;
assert_eq!(*map.get("Johnny").unwrap(), 22);

let _result1_locking = map.get("Johnny");

let result2 = map.try_get_mut("Johnny");
assert!(result2.is_locked());
```

--------------------------------

### Try to get immutable reference with try_get

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Attempts to get an immutable reference without blocking. Returns TryResult::Locked if the shard is currently locked.

```rust
use dashmap::DashMap;
use dashmap::try_result::TryResult;

let map = DashMap::new();
map.insert("Johnny", 21);

assert_eq!(*map.try_get("Johnny").unwrap(), 21);

let _result1_locking = map.get_mut("Johnny");

let result2 = map.try_get("Johnny");
assert!(result2.is_locked());
```

--------------------------------

### remove_if() examples: conditional removal (false and true conditions)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Two examples showing `remove_if` with a condition that returns false (entry remains) and true (entry removed). May deadlock if called while holding any reference into the map.

```rust
use dashmap::DashMap;

let soccer_team = DashMap::new();
soccer_team.insert("Sam", "Forward");
soccer_team.remove_if("Sam", |_, position| position == &"Goalie");
assert!(soccer_team.contains_key("Sam"));
```

```rust
use dashmap::DashMap;

let soccer_team = DashMap::new();
soccer_team.insert("Sam", "Forward");
soccer_team.remove_if("Sam", |_, position| position == &"Forward");
assert!(!soccer_team.contains_key("Sam"));
```

--------------------------------

### Create a DashMap with with_hasher()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a capacity of 0 and a provided hasher, then inserts a key-value pair.

```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let reviews = DashMap::with_hasher(s);
reviews.insert("Veloren", "What a fantastic game!");
```

--------------------------------

### Create a DashMap with with_capacity_and_shard_amount()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a specified capacity and shard amount. The shard amount must be greater than 0 and a power of two; otherwise the function panics.

```rust
use dashmap::DashMap;

let mappings = DashMap::with_capacity_and_shard_amount(32, 32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

--------------------------------

### Create a DashMap with with_hasher_and_shard_amount()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a specified hasher and shard amount. The shard amount must be greater than 0 and a power of two; otherwise the function panics.

```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let mappings = DashMap::with_hasher_and_shard_amount(s, 32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

--------------------------------

### Get DashSet length

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Use len to retrieve the total number of elements currently stored in the set.

```rust
use dashmap::DashSet;

let people = DashSet::new();
people.insert("Albin");
people.insert("Jones");
people.insert("Charlie");
assert_eq!(people.len(), 3);
```

--------------------------------

### new()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a capacity of 0.

```APIDOC
## new()

### Description
Creates a new DashMap with a capacity of 0.

### Method
new

### Parameters
None

### Request Example
```rust
use dashmap::DashMap;

let reviews = DashMap::new();
reviews.insert("Veloren", "What a fantastic game!");
```

### Response
Returns a new DashMap instance.
```

--------------------------------

### get_mut

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Get a mutable reference to an entry in the map. May deadlock if called when holding any sort of reference into the map.

```APIDOC
## get_mut(key)

### Description
Get a mutable reference to an entry in the map.

### Method
get_mut

### Signature
pub fn get_mut<Q>(&'a self, key: &Q) -> Option<RefMut<'a, K, V>>
where K: Borrow<Q>, Q: Hash + Eq + ?Sized,

### Parameters
- **key** (&Q) - Required - The key to look up.

### Locking Behaviour
May deadlock if called when holding any sort of reference into the map.

### Example
```rust
use dashmap::DashMap;

let class = DashMap::new();
class.insert("Albin", 15);
*class.get_mut("Albin").unwrap() -= 1;
assert_eq!(*class.get("Albin").unwrap(), 14);
```
```

--------------------------------

### try_upgradable_read_until

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Attempts to acquire this RwLock with upgradable read access until a specific instant is reached.

```APIDOC
## try_upgradable_read_until

### Description
Attempts to acquire this `RwLock` with upgradable read access until a timeout is reached. If the access could not be granted before the timeout expires, then `None` is returned. Otherwise, an RAII guard is returned which will release the shared access when it is dropped.

### Signature
`pub fn try_upgradable_read_until(&self, timeout: <R as RawRwLockTimed>::Instant) -> Option<RwLockUpgradableReadGuard<'_, R, T>>`

### Parameters
- `timeout` (`<R as RawRwLockTimed>::Instant`): The absolute time to wait until for the lock.

### Returns
- `Option<RwLockUpgradableReadGuard<'_, R, T>>`: The guard if acquired, `None` if timed out.

```

--------------------------------

### Create a DashMap with with_shard_amount()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a specified shard amount. The shard amount must be greater than 0 and a power of two; otherwise the function panics.

```rust
use dashmap::DashMap;

let mappings = DashMap::with_shard_amount(32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

--------------------------------

### try_get_mut

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Get a mutable reference to an entry in the map, if the shard is not locked. If the shard is locked, the function will return TryResult::Locked.

```APIDOC
## try_get_mut(key)

### Description
Get a mutable reference to an entry in the map, if the shard is not locked. If the shard is locked, the function will return TryResult::Locked.

### Method
try_get_mut

### Signature
pub fn try_get_mut<Q>(&'a self, key: &Q) -> TryResult<RefMut<'a, K, V>>
where K: Borrow<Q>, Q: Hash + Eq + ?Sized,

### Parameters
- **key** (&Q) - Required - The key to look up.

### Example
```rust
use dashmap::DashMap;
use dashmap::try_result::TryResult;

let map = DashMap::new();
map.insert("Johnny", 21);

*map.try_get_mut("Johnny").unwrap() += 1;
assert_eq!(*map.get("Johnny").unwrap(), 22);

let _result1_locking = map.get("Johnny");

let result2 = map.try_get_mut("Johnny");
assert!(result2.is_locked());
```
```

--------------------------------

### try_upgradable_read

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Attempts to acquire this RwLock with upgradable read access. Returns None if the access could not be granted immediately.

```APIDOC
## try_upgradable_read

### Description
Attempts to acquire this `RwLock` with upgradable read access. If the access could not be granted at this time, then `None` is returned. Otherwise, an RAII guard is returned which will release the shared access when it is dropped. This function does not block.

### Signature
`pub fn try_upgradable_read(&self) -> Option<RwLockUpgradableReadGuard<'_, R, T>>`

### Returns
- `Option<RwLockUpgradableReadGuard<'_, R, T>>`: The guard if acquired, `None` otherwise.

```

--------------------------------

### try_get

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Get an immutable reference to an entry in the map, if the shard is not locked. If the shard is locked, the function will return TryResult::Locked.

```APIDOC
## try_get(key)

### Description
Get an immutable reference to an entry in the map, if the shard is not locked. If the shard is locked, the function will return TryResult::Locked.

### Method
try_get

### Signature
pub fn try_get<Q>(&'a self, key: &Q) -> TryResult<Ref<'a, K, V>>
where K: Borrow<Q>, Q: Hash + Eq + ?Sized,

### Parameters
- **key** (&Q) - Required - The key to look up.

### Example
```rust
use dashmap::DashMap;
use dashmap::try_result::TryResult;

let map = DashMap::new();
map.insert("Johnny", 21);

assert_eq!(*map.try_get("Johnny").unwrap(), 21);

let _result1_locking = map.get_mut("Johnny");

let result2 = map.try_get("Johnny");
assert!(result2.is_locked());
```
```

--------------------------------

### Get mutable reference with get_mut

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Retrieves a mutable reference to an entry. May deadlock if called while holding any reference into the map.

```rust
use dashmap::DashMap;

let class = DashMap::new();
class.insert("Albin", 15);
*class.get_mut("Albin").unwrap() -= 1;
assert_eq!(*class.get("Albin").unwrap(), 14);
```

--------------------------------

### with_capacity_and_shard_amount(capacity: usize, shard_amount: usize)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a specified capacity and shard amount.

```APIDOC
## with_capacity_and_shard_amount(capacity: usize, shard_amount: usize)

### Description
Creates a new DashMap with a specified capacity and shard amount. The shard amount must be greater than 0 and a power of two; otherwise, the function will panic.

### Method
with_capacity_and_shard_amount

### Parameters
- **capacity** (usize) - Required - The initial capacity of the map.
- **shard_amount** (usize) - Required - The number of shards to use. Must be greater than 0 and a power of two.

### Request Example
```rust
use dashmap::DashMap;

let mappings = DashMap::with_capacity_and_shard_amount(32, 32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

### Response
Returns a new DashMap instance with the specified capacity and shard amount.
```

--------------------------------

### Get map length with len

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Returns the total number of key-value pairs. May deadlock if called while holding a mutable reference.

```rust
use dashmap::DashMap;

let people = DashMap::new();
people.insert("Albin", 15);
people.insert("Jones", 22);
people.insert("Charlie", 27);
assert_eq!(people.len(), 3);
```

--------------------------------

### take

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.IterMut.html

Creates an iterator that yields the first `n` elements, or fewer if the underlying iterator ends sooner.

```APIDOC
## take

### Description
Creates an iterator that yields the first `n` elements, or fewer if the underlying iterator ends sooner.

### Method
take

### Signature
```rust
fn take(self, n: usize) -> Take<Self>
where
    Self: Sized,
```

### Parameters
- **n** (usize) - Required - The number of elements to take.

### Return Value
- **Take<Self>** - An iterator adapter that yields at most `n` elements.
```

--------------------------------

### from_raw

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Creates a new RwLock from a raw lock and value.

```APIDOC
## from_raw

### Description
Creates a new instance of an `RwLock<T>` based on a pre-existing `RawRwLock<T>`.

### Signature
`pub const fn from_raw(raw_rwlock: R, val: T) -> RwLock<R, T>`

### Parameters
- `raw_rwlock` (`R`): The raw lock instance.
- `val` (`T`): The initial value.

### Returns
- `RwLock<R, T>`: The newly created lock.

```

--------------------------------

### Create a DashMap with new()

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a DashMap with a capacity of 0 and inserts a key-value pair.

```rust
use dashmap::DashMap;

let reviews = DashMap::new();
reviews.insert("Veloren", "What a fantastic game!");
```

--------------------------------

### with_hasher_and_shard_amount(hasher: S, shard_amount: usize)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a specified hasher and shard amount.

```APIDOC
## with_hasher_and_shard_amount(hasher: S, shard_amount: usize)

### Description
Creates a new DashMap with a specified hasher and shard amount. The shard amount must be greater than 0 and a power of two; otherwise, the function will panic.

### Method
with_hasher_and_shard_amount

### Parameters
- **hasher** (S) - Required - The hasher to use for hashing keys.
- **shard_amount** (usize) - Required - The number of shards to use. Must be greater than 0 and a power of two.

### Request Example
```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let mappings = DashMap::with_hasher_and_shard_amount(s, 32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

### Response
Returns a new DashMap instance with the specified hasher and shard amount.
```

--------------------------------

### with_hasher(hasher: S)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a capacity of 0 and the provided hasher.

```APIDOC
## with_hasher(hasher: S)

### Description
Creates a new DashMap with a capacity of 0 and the provided hasher.

### Method
with_hasher

### Parameters
- **hasher** (S) - Required - The hasher to use for hashing keys.

### Request Example
```rust
use dashmap::DashMap;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let reviews = DashMap::with_hasher(s);
reviews.insert("Veloren", "What a fantastic game!");
```

### Response
Returns a new DashMap instance with the specified hasher.
```

--------------------------------

### into_inner

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Consumes the RwLock and returns the underlying data.

```APIDOC
## into_inner

### Description
Consumes this `RwLock`, returning the underlying data.

### Signature
`pub fn into_inner(self) -> T`

### Returns
The underlying value of the lock.

```

--------------------------------

### DashSet::new

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Creates a new DashSet with a capacity of 0.

```APIDOC
## new

### Description
Creates a new DashSet with a capacity of 0.

### Method
new

### Parameters
None

### Request Example
```rust
use dashmap::DashSet;

let games = DashSet::new();
games.insert("Veloren");
```

### Response
#### Success Response
- **Self** - A new DashSet instance.

#### Response Example
```rust
let games = DashSet::new();
```
```

--------------------------------

### take_any

Source: https://docs.rs/dashmap/6.2.1/dashmap/rayon/map/struct.IterMut.html

Creates an iterator that yields n elements from anywhere in the original iterator.

```APIDOC
## take_any

### Description
Creates an iterator that yields `n` elements from _anywhere_ in the original iterator.

### Method
take_any

### Signature
```rust
fn take_any(self, n: usize) -> TakeAny<Self>
```

### Parameters
- `n` (usize) - Required - The number of elements to yield.

### Returns
- `TakeAny<Self>` - An iterator that yields `n` elements from anywhere in the original iterator.
```

--------------------------------

### force_unlock_write

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Forcibly unlocks a write lock. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockWriteGuard` object alive, for example when dealing with FFI.

```APIDOC
## force_unlock_write

### Description
Forcibly unlocks a write lock. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockWriteGuard` object alive, for example when dealing with FFI.

### Method
unsafe fn

### Signature
`pub unsafe fn force_unlock_write(&self)`

### Safety
This method must only be called if the current thread logically owns a `RwLockWriteGuard` but that guard has be discarded using `mem::forget`. Behavior is undefined if a rwlock is write-unlocked when not write-locked.

```

--------------------------------

### partition

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.IterMut.html

Consumes an iterator, creating two collections from it.

```APIDOC
## partition

### Description
Consumes an iterator, creating two collections from it.

### Method
partition

### Signature
```rust
fn partition<B, F>(self, f: F) -> (B, B)
where
    Self: Sized,
    B: Default + Extend<Self::Item>,
    F: FnMut(&Self::Item) -> bool,
```

### Parameters
- **f** (F) - Required - A closure that takes a reference to an item and returns a boolean indicating which collection the item belongs to.

### Return Value
- **(B, B)** - A tuple of two collections: the first contains items for which `f` returned `true`, the second contains the rest.
```

--------------------------------

### force_unlock_read

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Forcibly unlocks a read lock. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockReadGuard` object alive, for example when dealing with FFI.

```APIDOC
## force_unlock_read

### Description
Forcibly unlocks a read lock. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockReadGuard` object alive, for example when dealing with FFI.

### Method
unsafe fn

### Signature
`pub unsafe fn force_unlock_read(&self)`

### Safety
This method must only be called if the current thread logically owns a `RwLockReadGuard` but that guard has be discarded using `mem::forget`. Behavior is undefined if a rwlock is read-unlocked when not read-locked.

```

--------------------------------

### try_upgradable_read_for

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Attempts to acquire this RwLock with upgradable read access until a timeout is reached.

```APIDOC
## try_upgradable_read_for

### Description
Attempts to acquire this `RwLock` with upgradable read access until a timeout is reached. If the access could not be granted before the timeout expires, then `None` is returned. Otherwise, an RAII guard is returned which will release the shared access when it is dropped.

### Signature
`pub fn try_upgradable_read_for(&self, timeout: <R as RawRwLockTimed>::Duration) -> Option<RwLockUpgradableReadGuard<'_, R, T>>`

### Parameters
- `timeout` (`<R as RawRwLockTimed>::Duration`): The maximum duration to wait for the lock.

### Returns
- `Option<RwLockUpgradableReadGuard<'_, R, T>>`: The guard if acquired within the timeout, `None` if timed out.

```

--------------------------------

### data_ptr

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Returns a raw pointer to the underlying data. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockReadGuard` or `RwLockWriteGuard` object alive, for example when dealing with FFI.

```APIDOC
## data_ptr

### Description
Returns a raw pointer to the underlying data. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockReadGuard` or `RwLockWriteGuard` object alive, for example when dealing with FFI.

### Method
fn

### Signature
`pub fn data_ptr(&self) -> *mut T`

### Safety
You must ensure that there are no data races when dereferencing the returned pointer, for example if the current thread logically owns a `RwLockReadGuard` or `RwLockWriteGuard` but that guard has been discarded using `mem::forget`.

```

--------------------------------

### OwningIter::next

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.OwningIter.html

Advances the iterator and returns the next key-value pair as an Option<(K, V)>.

```APIDOC
## OwningIter::next

### Description
Advances the iterator and returns the next value.

### Method
`fn next(&mut self) -> Option<Self::Item>`

### Parameters
- `self` (mutable reference) - The iterator instance.

### Returns
- `Option<(K, V)>` - The next key-value pair, or `None` if iteration is complete.

### Example
```rust
use dashmap::DashMap;

let map = DashMap::new();
map.insert("hello", "world");
map.insert("alex", "steve");
let mut iter = map.into_iter();
while let Some((k, v)) = iter.next() {
    println!("{}: {}", k, v);
}
```
```

--------------------------------

### with_shard_amount(shard_amount: usize)

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Creates a new DashMap with a specified shard amount.

```APIDOC
## with_shard_amount(shard_amount: usize)

### Description
Creates a new DashMap with a specified shard amount. The shard amount must be greater than 0 and a power of two; otherwise, the function will panic.

### Method
with_shard_amount

### Parameters
- **shard_amount** (usize) - Required - The number of shards to use. Must be greater than 0 and a power of two.

### Request Example
```rust
use dashmap::DashMap;

let mappings = DashMap::with_shard_amount(32);
mappings.insert(2, 4);
mappings.insert(8, 16);
```

### Response
Returns a new DashMap instance with the specified shard amount.
```

--------------------------------

### Iterating and mutating values with iter_mut

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.IterMut.html

Example usage of iter_mut() to iterate over a DashMap and mutate each value. It inserts a key-value pair, increments the value by 1 using for_each, and asserts the updated value is 22.

```rust
use dashmap::DashMap;

let map = DashMap::new();
map.insert("Johnny", 21);
map.iter_mut().for_each(|mut r| *r += 1);
assert_eq!(*map.get("Johnny").unwrap(), 22);
```

--------------------------------

### Create a DashSet with a hasher

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Creates a new DashSet with a capacity of 0 and the provided hasher.

```rust
use dashmap::DashSet;
use std::collections::hash_map::RandomState;

let s = RandomState::new();
let games = DashSet::with_hasher(s);
games.insert("Veloren");
```

--------------------------------

### force_unlock_write_fair

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Forcibly unlocks a write lock using a fair unlock protocol. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockWriteGuard` object alive, for example when dealing with FFI.

```APIDOC
## force_unlock_write_fair

### Description
Forcibly unlocks a write lock using a fair unlock protocol. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockWriteGuard` object alive, for example when dealing with FFI.

### Method
unsafe fn

### Signature
`pub unsafe fn force_unlock_write_fair(&self)`

### Safety
This method must only be called if the current thread logically owns a `RwLockWriteGuard` but that guard has be discarded using `mem::forget`. Behavior is undefined if a rwlock is write-unlocked when not write-locked.
```

--------------------------------

### force_unlock_read_fair

Source: https://docs.rs/dashmap/6.2.1/dashmap/type.RwLock.html

Forcibly unlocks a read lock using a fair unlock protocol. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockReadGuard` object alive, for example when dealing with FFI.

```APIDOC
## force_unlock_read_fair

### Description
Forcibly unlocks a read lock using a fair unlock protocol. This is useful when combined with `mem::forget` to hold a lock without the need to maintain a `RwLockReadGuard` object alive, for example when dealing with FFI.

### Method
unsafe fn

### Signature
`pub unsafe fn force_unlock_read_fair(&self)`

### Safety
This method must only be called if the current thread logically owns a `RwLockReadGuard` but that guard has be discarded using `mem::forget`. Behavior is undefined if a rwlock is read-unlocked when not read-locked.
```

--------------------------------

### entry

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Advanced entry API that tries to mimic `std::collections::HashMap`.

```APIDOC
## entry

### Description
Advanced entry API that tries to mimic `std::collections::HashMap`. See the documentation on `dashmap::mapref::entry` for more details.

### Method
N/A

### Endpoint
N/A

### Parameters
#### Function Parameters
- **key** (`K`) - Required - The key to get an entry for.

### Request Example
```rust
// No example provided in source
```

### Response
#### Success Response
- Returns `Entry<'a, K, V>` - The entry for the given key.

#### Response Example
```rust
// No example provided in source
```

### Errors
- **Locking**: May deadlock if called when holding any sort of reference into the map.
```

--------------------------------

### by_ref

Source: https://docs.rs/dashmap/6.2.1/dashmap/iter/struct.IterMut.html

Creates a “by reference” adapter for this instance of `Iterator`.

```APIDOC
## by_ref

### Description
Creates a “by reference” adapter for this instance of `Iterator`.

### Method
by_ref

### Signature
```rust
fn by_ref(&mut self) -> &mut Self
where
    Self: Sized,
```

### Return Value
- **&mut Self** - A mutable reference to the iterator, allowing it to be consumed partially.
```

--------------------------------

### into_shards

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashMap.html

Consumes this `DashMap` and returns the inner shards. You should probably not use this unless you know what you are doing. Requires the `raw-api` feature to be enabled. See `DashMap::shards()` and `DashMap::shards_mut()` for more information.

```APIDOC
## into_shards

### Description
Consumes this `DashMap` and returns the inner shards. You should probably not use this unless you know what you are doing. Requires the `raw-api` feature to be enabled. See `DashMap::shards()` and `DashMap::shards_mut()` for more information.

### Method
into_shards

### Parameters
None

### Response
Returns the inner shards as a boxed slice.

```

--------------------------------

### Create a new DashSet

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.DashSet.html

Creates a new DashSet with a capacity of 0.

```rust
use dashmap::DashSet;

let games = DashSet::new();
games.insert("Veloren");
```

--------------------------------

### product

Source: https://docs.rs/dashmap/6.2.1/dashmap/rayon/map/struct.IterMut.html

Multiplies all the items in the iterator.

```APIDOC
## product<P>(self) -> P

### Description
Multiplies all the items in the iterator.

### Method
product

### Type Constraints
- `P: Send + Product<Self::Item> + Product`

### Returns
- `P` - The product of all items.
```

--------------------------------

### product

Source: https://docs.rs/dashmap/6.2.1/dashmap/rayon/map/struct.Iter.html

Computes the product of all items in the iterator.

```APIDOC
## product

### Description
Multiplies all the items in the iterator.

### Method
product

### Signature
`fn product<P>(self) -> P`

### Type Parameters
- `P` (Send + Product<Self::Item> + Product) - The type of the product.

### Returns
- `P` - The product of all items.
```

--------------------------------

### Ref::pair

Source: https://docs.rs/dashmap/6.2.1/dashmap/mapref/one/struct.Ref.html

Returns a tuple of references to the key and value of the entry.

```APIDOC
## Ref::pair

### Description
Returns a tuple of references to the key and value of the entry.

### Method
pair

### Signature
pub fn pair(&self) -> (&K, &V)

### Parameters
None

### Returns
- **(&K, &V)** - A tuple containing references to the key and value.

```

--------------------------------

### into_inner

Source: https://docs.rs/dashmap/6.2.1/dashmap/struct.ReadOnlyView.html

Consumes the `ReadOnlyView` and returns the underlying `DashMap`.

```APIDOC
## into_inner

### Description
Consumes this `ReadOnlyView`, returning the underlying `DashMap`.

### Method
into_inner

### Signature
`pub fn into_inner(self) -> DashMap<K, V, S>`

### Parameters
- `self` - The `ReadOnlyView` to consume.

### Returns
- `DashMap<K, V, S>` - The underlying `DashMap`.
```
Tokens:
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