commit | 2d311a4169a9a831de4deecd31663bfb996e23ca | [log] [tgz] |
---|---|---|
author | Android Build Coastguard Worker <[email protected]> | Thu Feb 17 02:57:53 2022 +0000 |
committer | Android Build Coastguard Worker <[email protected]> | Thu Feb 17 02:57:53 2022 +0000 |
tree | 3b1504f99e3af24d7ff3099804413156a07ffab5 | |
parent | f53d16b43cc6daf53174998643228f5d45d6bf26 [diff] | |
parent | a3c757545f3449a212d1f23b39a87b8e04d88360 [diff] |
Snap for 8191477 from a3c757545f3449a212d1f23b39a87b8e04d88360 to tm-frc-media-swcodec-release Change-Id: I04d975f9ac6d1358a04a22c19d82d84e0c97c230
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.