commit	09e04cbe2061aa8a93d86ce92abf4a2b8cedd6f5	[log] [tgz]
author	Linux Build Service Account <lnxbuild@localhost>	Sun Apr 18 10:45:37 2021 -0700
committer	Linux Build Service Account <lnxbuild@localhost>	Sun Apr 18 10:45:37 2021 -0700
tree	de0cbf8187347d699e8fbb7291d2749ff1a4b336
parent	c16771c10fbb1195382a06b10cf0a063dd854541 [diff]
parent	8ec29176898dee03f743af2788f7d593ab2dca9a [diff]

tree: de0cbf8187347d699e8fbb7291d2749ff1a4b336

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