An implementation of Ruby's pseudo-random number generator, or PRNG.
The PRNG produces a deterministic sequence of bits which approximate true randomness. The sequence may be represented by integers, floats, or binary strings.
The generator may be initialized with either a system-generated or user-supplied seed value.
PRNGs are currently implemented as a modified Mersenne Twister with a period of 2**19937-1.
This RNG reproduces the same random bytes and floats as MRI. It may differ when returning elements confined to a distribution.
let seed = [627457_u32, 697550, 16438, 41926]; let mut random = Random::with_array_seed(seed); let rand = random.next_int32();
Generate random numbers in a range:
let mut random = Random::new()?; let max = Max::Integer(10); let mut rand = rand(&mut random, max)?; assert!(matches!(rand, Rand::Integer(x) if x < 10));
This crate is
no_std compatible when built without the
std feature. This
crate does not depend on
All features are enabled by default.
- random-rand - Enables range sampling methods for the
rand()function. Activating this feature also activates the rand-traits feature. Dropping this feature removes the
- rand-traits - Enables implementations of
Mttypes. Dropping this feature removes the
- std - Enables a dependency on the Rust Standard Library. Activating
this feature enables
std::error::Errorimpls on error types in this crate.
Error that indicates a random number could not be generated with the given bounds.
Error that indicates a
The 32-bit Ruby flavor of the Mersenne Twister pseudorandom number generator.
Error that indicates the system source of cryptographically secure randomness failed to read sufficient bytes to create a new seed.
Random provides an interface to Ruby's pseudo-random number generator, or PRNG.
Error that indicates the system source of cryptographically secure randomness failed to read the requested bytes.
Sum type of all errors possibly returned from
A range constraint for generating random numbers.
A generated random number.
Read a new
Generate random numbers bounded from below by 0 and above by the given max.
Convert a byte array into a reseeding key of
Read random bytes, using platform-provided randomness.