commit | 10b6208d2e7bd3e12f65f44bcfa071c6b430d2be | [log] [tgz] |
---|---|---|
author | Android Build Coastguard Worker <[email protected]> | Wed May 11 05:06:29 2022 +0000 |
committer | Android Build Coastguard Worker <[email protected]> | Wed May 11 05:06:29 2022 +0000 |
tree | 3b1504f99e3af24d7ff3099804413156a07ffab5 | |
parent | 3d7279c7b3973433ce44028a3cad8801cc727586 [diff] | |
parent | a3c757545f3449a212d1f23b39a87b8e04d88360 [diff] |
Snap for 8570526 from a3c757545f3449a212d1f23b39a87b8e04d88360 to mainline-mediaprovider-release Change-Id: Ie68e6a7527ab4e3b0a7c481ff06dcd802b297156
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.