Snap for 8006021 from a3c757545f3449a212d1f23b39a87b8e04d88360 to tm-release

Change-Id: Ic2fa9eb7077b5fcaf0de4df33be819d79d83249f
tree: 3b1504f99e3af24d7ff3099804413156a07ffab5
  1. .github/
  2. benches/
  3. src/
  4. tests/
  5. .cargo_vcs_info.json
  6. .clippy.toml
  7. .gitignore
  8. Android.bp
  9. Cargo.toml
  10. Cargo.toml.orig
  11. cargo2android.json
  12. LICENSE
  13. LICENSE-APACHE
  14. LICENSE-MIT
  15. METADATA
  16. MODULE_LICENSE_APACHE2
  17. OWNERS
  18. README.md
  19. TEST_MAPPING
README.md

itoa

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"

Performance (lower is better)

performance

Examples

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.

License