commit | 17a8b6c93d5ebf1c50f92d30a5d2cc56748d8c9b | [log] [tgz] |
---|---|---|
author | Android Build Role Account android-build-prod <android-build-team-robot@google.com> | Thu Nov 05 11:02:09 2020 +0000 |
committer | Android Build Role Account android-build-prod <android-build-team-robot@google.com> | Thu Nov 05 11:02:09 2020 +0000 |
tree | 10c0471b78971f94c4027fd815f064d241dd8adf | |
parent | 4ec7f140203d656f985709aa5897b531ae178691 [diff] | |
parent | 0ff2ae5a1dbfd19bb3a1baee24b9701dfd2254d7 [diff] |
Snap for 6953696 from 0ff2ae5a1dbfd19bb3a1baee24b9701dfd2254d7 to s-keystone-qcom-release Change-Id: I95d0ca6b667597131fda13847512f29a269e34b5
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.