const-hex 1.3.0

Fast byte array to hex string conversion
Documentation 
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# const-hex

[![github](https://img.shields.io/badge/github-danipopes/const--hex-8da0cb?style=for-the-badge&labelColor=555555&logo=github)](https://github.com/danipopes/const-hex)
[![crates.io](https://img.shields.io/crates/v/const-hex.svg?style=for-the-badge&color=fc8d62&logo=rust)](https://crates.io/crates/const-hex)
[![docs.rs](https://img.shields.io/badge/docs.rs-const--hex-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs)](https://docs.rs/const-hex)
[![build status](https://img.shields.io/github/actions/workflow/status/danipopes/const-hex/ci.yml?branch=master&style=for-the-badge)](https://github.com/danipopes/const-hex/actions?query=branch%3Amaster)

This crate provides a fast conversion of byte arrays to hexadecimal strings,
both at compile time, and at run time.

Extends the [`hex`] crate's implementation with [const-eval], a
[const-generics formatting buffer][buffer], similar to [`itoa`]'s, and more.

_Version requirement: rustc 1.64+_

[const-eval]: https://docs.rs/const-hex/latest/const-hex/fn.const_encode.html
[buffer]: https://docs.rs/const-hex/latest/const-hex/struct.Buffer.html
[`itoa`]: https://docs.rs/itoa/latest/itoa/struct.Buffer.html

## Performance

This crate is ~10 times faster than [`hex`] in encoding, and 30+ times faster
than `libstd` in formatting.

You can run the following benchmarks with `cargo bench` on a nightly compiler.

```log
test encode_const_hex::bench1_32   ... bench:           1 ns/iter (+/- 0)
test encode_const_hex::bench2_128  ... bench:           5 ns/iter (+/- 0)
test encode_const_hex::bench3_4096 ... bench:         204 ns/iter (+/- 9)
test encode_hex::bench1_32         ... bench:          15 ns/iter (+/- 1)
test encode_hex::bench2_128        ... bench:          60 ns/iter (+/- 2)
test encode_hex::bench3_4096       ... bench:       1,703 ns/iter (+/- 50)
test format_const_hex::bench1_32   ... bench:          15 ns/iter (+/- 0)
test format_const_hex::bench2_128  ... bench:          20 ns/iter (+/- 0)
test format_const_hex::bench3_4096 ... bench:         380 ns/iter (+/- 9)
test format_std::bench1_32         ... bench:         470 ns/iter (+/- 4)
test format_std::bench2_128        ... bench:       1,961 ns/iter (+/- 17)
test format_std::bench3_4096       ... bench:      61,688 ns/iter (+/- 1,994)
```

## Acknowledgements

-   [`hex`] for most of the formatting implementation
-   [dtolnay]/[itoa] for the initial crate/library API layout

[`hex`]: https://crates.io/crates/hex
[dtolnay]: https://github.com/dtolnay
[itoa]: https://github.com/dtolnay/itoa

## License

Licensed under either of [Apache License, Version 2.0](./LICENSE-APACHE) or
[MIT license](./LICENSE-MIT) at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
be dual licensed as above, without any additional terms or conditions.