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dtoa
====
[<img alt="github" src="https://img.shields.io/badge/github-dtolnay/dtoa-8da0cb?style=for-the-badge&labelColor=555555&logo=github" height="20">](https://github.com/dtolnay/dtoa)
[<img alt="crates.io" src="https://img.shields.io/crates/v/dtoa.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/dtoa)
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This crate provides fast functions for printing floating-point primitives to an
[`io::Write`]. The implementation is a straightforward Rust port of [Milo Yip]'s
C++ implementation [dtoa.h]. The original C++ code of each function is included
in comments.
See also [`itoa`] for printing integer primitives.
*Version requirement: rustc 1.0+*
```toml
[dependencies]
dtoa = "0.4"
```
<br>
## Performance (lower is better)
<br>
## Examples
```rust
use std::io;
fn main() -> io::Result<()> {
// Write to a vector or other io::Write.
let mut buf = Vec::new();
dtoa::write(&mut buf, 2.71828f64)?;
println!("{:?}", buf);
// Write to a stack buffer.
let mut bytes = [b'\0'; 20];
let n = dtoa::write(&mut bytes[..], 2.71828f64)?;
println!("{:?}", &bytes[..n]);
Ok(())
}
```
The function signature is:
```rust
fn write<W: io::Write, V: dtoa::Floating>(writer: W, value: V) -> io::Result<()>;
```
where `dtoa::Floating` is implemented for f32 and f64. The return value gives
the number of bytes written.
<br>
#### License
<sup>
Licensed under either of <a href="LICENSE-APACHE">Apache License, Version
2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option.
</sup>
<br>
<sub>
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
be dual licensed as above, without any additional terms or conditions.
</sub>