# rand::read::ReadRng - Rust
API documentation for the Rust `ReadRng` struct in crate `rand`.
Keywords: rust, rustlang, rust-lang, ReadRng

# Struct rand::read::ReadRng [−] [src]

    pub struct ReadRng<R> {
        // some fields omitted
    }

An RNG that reads random bytes straight from a `Read`. This will work best with an infinite reader, but this is not required.

# Panics

It will panic if it there is insufficient data to fulfill a request.

# Example

    use rand::{read, Rng};

    let data = vec![1, 2, 3, 4, 5, 6, 7, 8];
    let mut rng = read::ReadRng::new(&data[..]);
    println!("{:x}", rng.gen::<u32>());

## Methods

### `impl<R: Read> ReadRng<R>`

#### `fn new(r: R) -> ReadRng<R>`

Create a new `ReadRng` from a `Read`.

## Trait Implementations

### `impl<R: Read> Rng for ReadRng<R>`

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

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

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

#### `fn next_f32(&mut self) -> f32`

#### `fn next_f64(&mut self) -> f64`

#### `fn gen<T: Rand>(&mut self) -> T where Self: Sized`

#### `fn gen_iter<'a, T: Rand>(&'a mut self) -> Generator<'a, T, Self> where Self: Sized`

#### `fn gen_range<T: PartialOrd + SampleRange>(&mut self, low: T, high: T) -> T where Self: Sized`

#### `fn gen_weighted_bool(&mut self, n: u32) -> bool where Self: Sized`

#### `fn gen_ascii_chars<'a>(&'a mut self) -> AsciiGenerator<'a, Self> where Self: Sized`

#### `fn choose<'a, T>(&mut self, values: &'a [T]) -> Option<&'a T> where Self: Sized`

#### `fn shuffle<T>(&mut self, values: &mut [T]) where Self: Sized`

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