| commit | 98df337bca8f4068ebad9f866af88a15bd6a7c83 | [log] [tgz] |
|---|---|---|
| author | android-build-team Robot <[email protected]> | Fri May 07 00:33:25 2021 +0000 |
| committer | android-build-team Robot <[email protected]> | Fri May 07 00:33:25 2021 +0000 |
| tree | a37d77a527c577f11a2c00f84694c9fd47b5617b | |
| parent | 11755b3b32a01f165cec0921f34202e133f86bbe [diff] | |
| parent | dcd7fa19f594224dda8ec327473448164332b258 [diff] |
Snap for 7343852 from dcd7fa19f594224dda8ec327473448164332b258 to sc-mainline-release Change-Id: Ifd0f592f7f431a728c0ee97f70ad2d5a1e9e3f99
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.