commit | c69bef84aedd1242ed637501db37eb86ff8bab06 | [log] [tgz] |
---|---|---|
author | Android Build Role Account android-build-prod <android-build-team-robot@google.com> | Sat May 15 10:03:56 2021 +0000 |
committer | Android Build Role Account android-build-prod <android-build-team-robot@google.com> | Sat May 15 10:03:56 2021 +0000 |
tree | a37d77a527c577f11a2c00f84694c9fd47b5617b | |
parent | 8ec29176898dee03f743af2788f7d593ab2dca9a [diff] | |
parent | 90734016bf2ef499d045ed443236b10f90af1ff3 [diff] |
Snap for 7364285 from 90734016bf2ef499d045ed443236b10f90af1ff3 to s-keystone-qcom-release Change-Id: I7036c92294bf509df748d77fe5ad7aac909a5227
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.