# [−] [src] Crate rand_core

Random number generation traits

This crate is mainly of interest to crates publishing implementations of [`RngCore`]. Other users are encouraged to use the `rand` crate instead which re-exports the main traits and error types.

[`RngCore`] is the core trait implemented by algorithmic pseudo-random number generators and external random-number sources.

[`SeedableRng`] is an extension trait for construction from fixed seeds and other random number generators.

[`Error`] is provided for error-handling. It is safe to use in `no_std` environments.

The [`impls`] and [`le`] sub-modules include a few small functions to assist implementation of [`RngCore`].

## Modules

block | The `BlockRngCore` trait and implementation helpers
impls | Helper functions for implementing `RngCore` functions.
le | Little-Endian utilities

## Structs

Error | Error type of random number generators

## Traits

CryptoRng | A marker trait used to indicate that an [`RngCore`] or `BlockRngCore` implementation is supposed to be cryptographically secure.
RngCore | The core of a random number generator.
SeedableRng | A random number generator that can be explicitly seeded.

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