commit | 5e9b5a87aa377b86f0e71849a6fc2dabcfb12414 | [log] [tgz] |
---|---|---|
author | Android Build Role Account android-build-prod <android-build-team-robot@google.com> | Fri Feb 19 11:04:21 2021 +0000 |
committer | Android Build Role Account android-build-prod <android-build-team-robot@google.com> | Fri Feb 19 11:04:21 2021 +0000 |
tree | fcbd51b8adf2d2ed89cee6ccad95ba1a594992eb | |
parent | 002ecdb7b9f9ff1078bf891340a055d4f6f9c8c3 [diff] | |
parent | 146b1583a22a77e95823509a5d161b55e7f587da [diff] |
Snap for 7156330 from 146b1583a22a77e95823509a5d161b55e7f587da to s-keystone-qcom-release Change-Id: Ie8c7fdc7f76ec75c0a86b09b557879932bf2e8c4
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"
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.