commit	a55a325017bb0296f19c14ebd4f63d5284f2fb77	[log] [tgz]
author	Treehugger Robot <treehugger-gerrit@google.com>	Wed Jun 15 21:41:17 2022 +0000
committer	Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>	Wed Jun 15 21:41:17 2022 +0000
tree	3b1504f99e3af24d7ff3099804413156a07ffab5
parent	d2c089cd75554645b1a177827d5e61ec64d2f5a6 [diff]
parent	baa2bcc59ad653e6bc45f4dfc3f9b77cbdabea2c [diff]

tree: 3b1504f99e3af24d7ff3099804413156a07ffab5

README.md

itoa

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+

[dependencies]
itoa = "0.4"

Performance (lower is better)

performance

Examples

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:

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.

itoa

Performance (lower is better)

Examples

License