Optimized serialization of hyphenated UUID ASCII representation to io::Write
sinks.
The two functions exported by this crate are write_lower and write_upper;
here are their signatures:
rust
fn write_lower<W: io::Write>(io: &mut W, uuid: &Uuid) -> io::Result<usize>;
fn write_upper<W: io::Write>(io: &mut W, uuid: &Uuid) -> io::Result<usize>;
An example of writing this out to a buffer would be
rust
let uuid = Uuid::from_str("e098d1f6-7e49-4c34-99f6-e9c6cef8fcce").unwrap();
let mut buf: Vec<u8> = Vec::with_capacity(36);
write_lower(&mut buf, &uuid).unwrap();
This performs approximately 10x better than the equivalent fmt::Display impl
from the uuid crate.
rust
let uuid = Uuid::from_str("e098d1f6-7e49-4c34-99f6-e9c6cef8fcce").unwrap();
let buf = format!("{}", uuid.hyphenated());
The benchmarks from these two approaches are as follows.
test benches::bench_fmt ... bench: 522 ns/iter (+/- 6)
test benches::bench_lower ... bench: 45 ns/iter (+/- 0)
To run them for yourself, the bench feature and nightly compiler should be used.
sh
cargo bench --feature bench