commit	e8c179cbf892ebcf97a8832f45be190ebb45ead7	[log] [tgz]
author	Android Build Coastguard Worker <android-build-coastguard-worker@google.com>	Fri Sep 24 03:05:00 2021 +0000
committer	Android Build Coastguard Worker <android-build-coastguard-worker@google.com>	Fri Sep 24 03:05:00 2021 +0000
tree	7be04ab17626897820feb54c5e7fb94b26b51a11
parent	67a05d014d0cf61291078ea3823fa32a58eba834 [diff]
parent	91ca2bf2b03f1c93e25ac6822eee3de256935983 [diff]

tree: 7be04ab17626897820feb54c5e7fb94b26b51a11

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