1itoa 2==== 3 4[<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) 5[<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) 6[<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) 7[<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) 8 9This crate provides fast functions for printing integer primitives to an 10[`io::Write`] or a [`fmt::Write`]. The implementation comes straight from 11[libcore] but avoids the performance penalty of going through 12[`fmt::Formatter`]. 13 14See also [`dtoa`] for printing floating point primitives. 15 16*Version requirement: rustc 1.0+* 17 18[`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html 19[`fmt::Write`]: https://doc.rust-lang.org/core/fmt/trait.Write.html 20[libcore]: https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L201-L254 21[`fmt::Formatter`]: https://doc.rust-lang.org/std/fmt/struct.Formatter.html 22[`dtoa`]: https://github.com/dtolnay/dtoa 23 24```toml 25[dependencies] 26itoa = "0.4" 27``` 28 29<br> 30 31## Performance (lower is better) 32 33 34 35<br> 36 37## Examples 38 39```rust 40use std::{fmt, io}; 41 42fn demo_itoa_write() -> io::Result<()> { 43 // Write to a vector or other io::Write. 44 let mut buf = Vec::new(); 45 itoa::write(&mut buf, 128u64)?; 46 println!("{:?}", buf); 47 48 // Write to a stack buffer. 49 let mut bytes = [0u8; 20]; 50 let n = itoa::write(&mut bytes[..], 128u64)?; 51 println!("{:?}", &bytes[..n]); 52 53 Ok(()) 54} 55 56fn demo_itoa_fmt() -> fmt::Result { 57 // Write to a string. 58 let mut s = String::new(); 59 itoa::fmt(&mut s, 128u64)?; 60 println!("{}", s); 61 62 Ok(()) 63} 64``` 65 66The function signatures are: 67 68```rust 69fn write<W: io::Write, V: itoa::Integer>(writer: W, value: V) -> io::Result<usize>; 70 71fn fmt<W: fmt::Write, V: itoa::Integer>(writer: W, value: V) -> fmt::Result; 72``` 73 74where `itoa::Integer` is implemented for i8, u8, i16, u16, i32, u32, i64, u64, 75i128, u128, isize and usize. 128-bit integer support requires rustc 1.26+ and 76the `i128` feature of this crate enabled. 77 78The `write` function is only available when the `std` feature is enabled 79(default is enabled). The return value gives the number of bytes written. 80 81<br> 82 83#### License 84 85<sup> 86Licensed under either of <a href="LICENSE-APACHE">Apache License, Version 872.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option. 88</sup> 89 90<br> 91 92<sub> 93Unless you explicitly state otherwise, any contribution intentionally submitted 94for inclusion in this crate by you, as defined in the Apache-2.0 license, shall 95be dual licensed as above, without any additional terms or conditions. 96</sub> 97