Trait Sink

Source

pub trait Sink {
    // Required method
    fn put(&mut self, bytes: &[u8]) -> Result<(), Full>;

    // Provided method
    fn remaining(&self) -> Option<usize> { ... }
}

Expand description

The output abstraction every writer takes.

put appends all of bytes or fails with Full. remaining reports how many more bytes fit, when the sink knows; writers that produce a value in several put calls check it first, so a sink that knows its room never holds half a value after an error.

§Examples

use parse_net::{Full, Sink};

/// A sink that keeps only the last byte it was given.
struct Last(Option<u8>);
impl Sink for Last {
    fn put(&mut self, bytes: &[u8]) -> Result<(), Full> {
        if let Some(&b) = bytes.last() {
            self.0 = Some(b);
        }
        Ok(())
    }
}

let mut last = Last(None);
parse_net::write::write_token(b"gzip", &mut last)?;
assert_eq!(last.0, Some(b'p'));