| .. | ||
| src | ||
| .cargo-checksum.json | ||
| Cargo.toml | ||
| CHANGELOG.md | ||
| COPYRIGHT | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| README.md | ||
rand_core
Core traits and error types of the rand library, plus tools for implementing RNGs.
This crate is intended for use when implementing the core trait, RngCore; it
defines the core traits to be implemented as well as several small functions to
aid in their implementation and types required for error handling.
The main rand crate re-exports most items defined in this crate, along with
tools to convert the integer samples generated by RngCore to many different
applications (including sampling from restricted ranges, conversion to floating
point, list permutations and secure initialisation of RNGs). Most users should
prefer to use the main rand crate.
Links:
Functionality
The rand_core crate provides:
- base random number generator traits
- error-reporting types
- functionality to aid implementation of RNGs
The traits and error types are also available via rand.
Versions
Rand libs have inter-dependencies and make use of the
semver trick in order to make traits
compatible across crate versions. (This is especially important for RngCore
and SeedableRng.) A few crate releases are thus compatibility shims,
depending on the next lib version (e.g. rand_core versions 0.2.2 and
0.3.1). This means, for example, that rand_core_0_4_0::SeedableRng and
rand_core_0_3_0::SeedableRng are distinct, incompatible traits, which can
cause build errors. Usually, running cargo update is enough to fix any issues.
Crate Features
rand_core supports no_std and alloc-only configurations, as well as full
std functionality. The differences between no_std and full std are small,
comprising RngCore support for Box<R> types where R: RngCore,
std::io::Read support for types supporting RngCore, and
extensions to the Error type's functionality.
The std feature is not enabled by default. This is primarily to avoid build
problems where one crate implicitly requires rand_core with std support and
another crate requires rand without std support. However, the rand crate
continues to enable std support by default, both for itself and rand_core.
The serde1 feature can be used to derive Serialize and Deserialize for RNG
implementations that use the BlockRng or BlockRng64 wrappers.
License
rand_core is distributed under the terms of both the MIT license and the
Apache License (Version 2.0).
See LICENSE-APACHE and LICENSE-MIT, and COPYRIGHT for details.