| itoa |
| ==== |
| |
| [<img alt="github" src="https://img.shields.io/badge/github-dtolnay/itoa-8da0cb?style=for-the-badge&labelColor=555555&logo=github" height="20">](https://github.com/dtolnay/itoa) |
| [<img alt="crates.io" src="https://img.shields.io/crates/v/itoa.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/itoa) |
| [<img alt="docs.rs" src="https://img.shields.io/badge/docs.rs-itoa-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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" height="20">](https://docs.rs/itoa) |
| [<img alt="build status" src="https://img.shields.io/github/workflow/status/dtolnay/itoa/CI/master?style=for-the-badge" height="20">](https://github.com/dtolnay/itoa/actions?query=branch%3Amaster) |
| |
| This crate provides fast functions for printing integer primitives to an |
| [`io::Write`] or a [`fmt::Write`]. The implementation comes straight from |
| [libcore] but avoids the performance penalty of going through |
| [`fmt::Formatter`]. |
| |
| See also [`dtoa`] for printing floating point primitives. |
| |
| *Version requirement: rustc 1.0+* |
| |
| [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html |
| [`fmt::Write`]: https://doc.rust-lang.org/core/fmt/trait.Write.html |
| [libcore]: https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L201-L254 |
| [`fmt::Formatter`]: https://doc.rust-lang.org/std/fmt/struct.Formatter.html |
| [`dtoa`]: https://github.com/dtolnay/dtoa |
| |
| ```toml |
| [dependencies] |
| itoa = "0.4" |
| ``` |
| |
| <br> |
| |
| ## Performance (lower is better) |
| |
| ![performance](https://raw.githubusercontent.com/dtolnay/itoa/master/performance.png) |
| |
| <br> |
| |
| ## Examples |
| |
| ```rust |
| use std::{fmt, io}; |
| |
| fn demo_itoa_write() -> io::Result<()> { |
| // Write to a vector or other io::Write. |
| let mut buf = Vec::new(); |
| itoa::write(&mut buf, 128u64)?; |
| println!("{:?}", buf); |
| |
| // Write to a stack buffer. |
| let mut bytes = [0u8; 20]; |
| let n = itoa::write(&mut bytes[..], 128u64)?; |
| println!("{:?}", &bytes[..n]); |
| |
| Ok(()) |
| } |
| |
| fn demo_itoa_fmt() -> fmt::Result { |
| // Write to a string. |
| let mut s = String::new(); |
| itoa::fmt(&mut s, 128u64)?; |
| println!("{}", s); |
| |
| Ok(()) |
| } |
| ``` |
| |
| The function signatures are: |
| |
| ```rust |
| fn write<W: io::Write, V: itoa::Integer>(writer: W, value: V) -> io::Result<usize>; |
| |
| fn fmt<W: fmt::Write, V: itoa::Integer>(writer: W, value: V) -> fmt::Result; |
| ``` |
| |
| where `itoa::Integer` is implemented for i8, u8, i16, u16, i32, u32, i64, u64, |
| i128, u128, isize and usize. 128-bit integer support requires rustc 1.26+ and |
| the `i128` feature of this crate enabled. |
| |
| The `write` function is only available when the `std` feature is enabled |
| (default is enabled). The return value gives the number of bytes written. |
| |
| <br> |
| |
| #### License |
| |
| <sup> |
| Licensed under either of <a href="LICENSE-APACHE">Apache License, Version |
| 2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option. |
| </sup> |
| |
| <br> |
| |
| <sub> |
| 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. |
| </sub> |