# [−] [src] Struct rand::rngs::ThreadRng

    pub struct ThreadRng { /* fields omitted */ }

The type returned by [`thread_rng`], essentially just a reference to the PRNG in thread-local memory.

`ThreadRng` uses the same PRNG as `StdRng` for security and performance. As hinted by the name, the generator is thread-local. `ThreadRng` is a handle to this generator and thus supports `Copy`, but not `Send` or `Sync`.

Unlike `StdRng`, `ThreadRng` uses the `ReseedingRng` wrapper to reseed the PRNG from fresh entropy every 64 kiB of random data. [`OsRng`] is used to provide seed data.

Note that the reseeding is done as an extra precaution against side-channel attacks and mis-use (e.g. if somehow weak entropy were supplied initially). The PRNG algorithms used are assumed to be secure.

## Trait Implementations

### `impl Clone for ThreadRng` [src]

#### `fn clone(&self) -> ThreadRng` [src]

Returns a copy of the value. Read more

#### `fn clone_from(&mut self, source: &Self)`1.0.0 [src]

Performs copy-assignment from `source`. Read more

### `impl Default for ThreadRng` [src]

#### `fn default() -> ThreadRng` [src]

Returns the "default value" for a type. Read more

### `impl Copy for ThreadRng` [src]

### `impl Debug for ThreadRng` [src]

#### `fn fmt(&self, f: &mut Formatter) -> Result` [src]

Formats the value using the given formatter. Read more

### `impl RngCore for ThreadRng` [src]

#### `fn next_u32(&mut self) -> u32` [src]

Return the next random `u32`. Read more

#### `fn next_u64(&mut self) -> u64` [src]

Return the next random `u64`. Read more

#### `fn fill_bytes(&mut self, dest: &mut [u8])` [src]

Fill `dest` with random data. Read more

#### `fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error>` [src]

Fill `dest` entirely with random data. Read more

### `impl CryptoRng for ThreadRng` [src]

## Auto Trait Implementations

### `impl !Send for ThreadRng`

### `impl !Sync for ThreadRng`

## Blanket Implementations

### `impl<R> Rng for R where
R: RngCore + ?Sized,` [src]

#### `fn gen<T>(&mut self) -> T where
Standard: Distribution<T>,` [src]

Return a random value supporting the [`Standard`] distribution. Read more

#### `fn gen_range<T: SampleUniform, B1, B2>(&mut self, low: B1, high: B2) -> T where
B1: SampleBorrow<T> + Sized,
B2: SampleBorrow<T> + Sized,` [src]

Generate a random value in the range [`low`, `high`), i.e. inclusive of `low` and exclusive of `high`. Read more

#### `fn sample<T, D: Distribution<T>>(&mut self, distr: D) -> T` [src]

Sample a new value, using the given distribution. Read more

####
ⓘImportant traits for DistIter<D, R, T>

### Important traits for DistIter<D, R, T>

`impl<D, R, T> Iterator for DistIter<D, R, T> where
D: Distribution<T>,
R: Rng, type Item = T;`
`fn sample_iter<T, D>(self, distr: D) -> DistIter<D, Self, T> where
D: Distribution<T>,
Self: Sized,` [src]

Create an iterator that generates values using the given distribution. Read more

#### `fn fill<T: AsByteSliceMut + ?Sized>(&mut self, dest: &mut T)` [src]

Fill `dest` entirely with random bytes (uniform value distribution), where `dest` is any type supporting [`AsByteSliceMut`], namely slices and arrays over primitive integer types (`i8`, `i16`, `u32`, etc.). Read more

#### `fn try_fill<T: AsByteSliceMut + ?Sized>(
&mut self,
dest: &mut T
) -> Result<(), Error>` [src]

Fill `dest` entirely with random bytes (uniform value distribution), where `dest` is any type supporting [`AsByteSliceMut`], namely slices and arrays over primitive integer types (`i8`, `i16`, `u32`, etc.). Read more

#### `fn gen_bool(&mut self, p: f64) -> bool` [src]

Return a bool with a probability `p` of being true. Read more

#### `fn gen_ratio(&mut self, numerator: u32, denominator: u32) -> bool` [src]

Return a bool with a probability of `numerator/denominator` of being true. I.e. `gen_ratio(2, 3)` has chance of 2 in 3, or about 67%, of returning true. If `numerator == denominator`, then the returned value is guaranteed to be `true`. If `numerator == 0`, then the returned value is guaranteed to be `false`. Read more

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

#### `fn from(t: T) -> T` [src]

Performs the conversion.

### `impl<T> ToOwned for T where
T: Clone,` [src]

#### `type Owned = T`

The resulting type after obtaining ownership.

#### `fn to_owned(&self) -> T` [src]

Creates owned data from borrowed data, usually by cloning. Read more

#### `fn clone_into(&self, target: &mut T)` [src]

🔬 This is a nightly-only experimental API. (`toowned_clone_into`)

recently added

Uses borrowed data to replace owned data, usually by cloning. Read more

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

#### `fn into(self) -> U` [src]

Performs the conversion.

### `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.

#### `fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>` [src]

Performs the conversion.

### `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.

#### `fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>` [src]

Performs the conversion.

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

#### `fn borrow_mut(&mut self) -> &mut T` [src]

Mutably borrows from an owned value. Read more

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

#### `fn borrow(&self) -> &T` [src]

Immutably borrows from an owned value. Read more

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

#### `fn type_id(&self) -> TypeId` [src]

Gets the `TypeId` of `self`. Read more

### `impl<V, T> VZip<V> for T where
V: MultiLane<T>,` [src]

#### `fn vzip(self) -> V` [src]

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