commit	0d34fef465f99e748c7327c3e9f18e168109c8a0	[log] [tgz]
author	Android Build Coastguard Worker <android-build-coastguard-worker@google.com>	Mon Jan 31 01:50:43 2022 +0000
committer	Android Build Coastguard Worker <android-build-coastguard-worker@google.com>	Mon Jan 31 01:50:43 2022 +0000
tree	3b1504f99e3af24d7ff3099804413156a07ffab5
parent	63784f2f5b191ccb84d60dd234c2d06626a98740 [diff]
parent	17e1b911378d7c9b3f3bef2a61bb4ecaec7c0199 [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