| //! [![github]](https://github.com/dtolnay/ryu) [![crates-io]](https://crates.io/crates/ryu) [![docs-rs]](https://docs.rs/ryu) |
| //! |
| //! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github |
| //! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust |
| //! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs |
| //! |
| //! <br> |
| //! |
| //! Pure Rust implementation of Ryū, an algorithm to quickly convert floating |
| //! point numbers to decimal strings. |
| //! |
| //! The PLDI'18 paper [*Ryū: fast float-to-string conversion*][paper] by Ulf |
| //! Adams includes a complete correctness proof of the algorithm. The paper is |
| //! available under the creative commons CC-BY-SA license. |
| //! |
| //! This Rust implementation is a line-by-line port of Ulf Adams' implementation |
| //! in C, [https://github.com/ulfjack/ryu][upstream]. |
| //! |
| //! [paper]: https://dl.acm.org/citation.cfm?id=3192369 |
| //! [upstream]: https://github.com/ulfjack/ryu |
| //! |
| //! # Example |
| //! |
| //! ``` |
| //! fn main() { |
| //! let mut buffer = ryu::Buffer::new(); |
| //! let printed = buffer.format(1.234); |
| //! assert_eq!(printed, "1.234"); |
| //! } |
| //! ``` |
| //! |
| //! ## Performance (lower is better) |
| //! |
| //! ![performance](https://raw.githubusercontent.com/dtolnay/ryu/master/performance.png) |
| //! |
| //! You can run upstream's benchmarks with: |
| //! |
| //! ```console |
| //! $ git clone https://github.com/ulfjack/ryu c-ryu |
| //! $ cd c-ryu |
| //! $ bazel run -c opt //ryu/benchmark |
| //! ``` |
| //! |
| //! And the same benchmark against our implementation with: |
| //! |
| //! ```console |
| //! $ git clone https://github.com/dtolnay/ryu rust-ryu |
| //! $ cd rust-ryu |
| //! $ cargo run --example upstream_benchmark --release |
| //! ``` |
| //! |
| //! These benchmarks measure the average time to print a 32-bit float and average |
| //! time to print a 64-bit float, where the inputs are distributed as uniform random |
| //! bit patterns 32 and 64 bits wide. |
| //! |
| //! The upstream C code, the unsafe direct Rust port, and the safe pretty Rust API |
| //! all perform the same, taking around 21 nanoseconds to format a 32-bit float and |
| //! 31 nanoseconds to format a 64-bit float. |
| //! |
| //! There is also a Rust-specific benchmark comparing this implementation to the |
| //! standard library which you can run with: |
| //! |
| //! ```console |
| //! $ cargo bench |
| //! ``` |
| //! |
| //! The benchmark shows Ryū approximately 2-5x faster than the standard library |
| //! across a range of f32 and f64 inputs. Measurements are in nanoseconds per |
| //! iteration; smaller is better. |
| //! |
| //! ## Formatting |
| //! |
| //! This library tends to produce more human-readable output than the standard |
| //! library's to\_string, which never uses scientific notation. Here are two |
| //! examples: |
| //! |
| //! - *ryu:* 1.23e40, *std:* 12300000000000000000000000000000000000000 |
| //! - *ryu:* 1.23e-40, *std:* 0.000000000000000000000000000000000000000123 |
| //! |
| //! Both libraries print short decimals such as 0.0000123 without scientific |
| //! notation. |
| |
| #![no_std] |
| #![doc(html_root_url = "https://docs.rs/ryu/1.0.11")] |
| #![allow( |
| clippy::cast_lossless, |
| clippy::cast_possible_truncation, |
| clippy::cast_possible_wrap, |
| clippy::cast_sign_loss, |
| clippy::checked_conversions, |
| clippy::doc_markdown, |
| clippy::expl_impl_clone_on_copy, |
| clippy::if_not_else, |
| clippy::many_single_char_names, |
| clippy::missing_panics_doc, |
| clippy::module_name_repetitions, |
| clippy::must_use_candidate, |
| clippy::similar_names, |
| clippy::too_many_lines, |
| clippy::unreadable_literal, |
| clippy::unseparated_literal_suffix, |
| clippy::wildcard_imports |
| )] |
| |
| mod buffer; |
| mod common; |
| mod d2s; |
| #[cfg(not(feature = "small"))] |
| mod d2s_full_table; |
| mod d2s_intrinsics; |
| #[cfg(feature = "small")] |
| mod d2s_small_table; |
| mod digit_table; |
| mod f2s; |
| mod f2s_intrinsics; |
| mod pretty; |
| |
| pub use crate::buffer::{Buffer, Float}; |
| |
| /// Unsafe functions that mirror the API of the C implementation of Ryū. |
| pub mod raw { |
| pub use crate::pretty::{format32, format64}; |
| } |