| commit | c0714fd9ae7f680a79c6ba772b21aec054d4a96c | [log] [tgz] |
|---|---|---|
| author | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Wed Feb 16 01:12:33 2022 +0000 |
| committer | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Wed Feb 16 01:12:33 2022 +0000 |
| tree | a37d77a527c577f11a2c00f84694c9fd47b5617b | |
| parent | a3c757545f3449a212d1f23b39a87b8e04d88360 [diff] | |
| parent | 3d7279c7b3973433ce44028a3cad8801cc727586 [diff] |
Snap for 8188146 from 3d7279c7b3973433ce44028a3cad8801cc727586 to tm-frc-ipsec-release Change-Id: If35e424389537d71b288ffe19276748621f681b5
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.