Trait TryWrite

Source

pub trait TryWrite {
    // Required method
    fn try_write_str(&mut self, s: &str) -> Result<(), Error>;

    // Provided method
    fn try_write_char(&mut self, c: char) -> Result<(), Error> { ... }
}

Expand description

Fallible write formatting implementation.

Required Methods§

Source

fn try_write_str(&mut self, s: &str) -> Result<(), Error>

Writes a string slice into this writer, returning whether the write succeeded.

This method can only succeed if the entire string slice was successfully written, and this method will not return until all data has been written or an error occurs.

§Errors

This function will return an instance of Error on error.

§Examples

use rune::alloc::fmt::TryWrite;
use rune::alloc::{String, Error};

fn writer<W: TryWrite>(f: &mut W, s: &str) -> Result<(), Error> {
    f.try_write_str(s)
}

let mut buf = String::new();
writer(&mut buf, "hola")?;
assert_eq!(&buf, "hola");

Provided Methods§

Source

fn try_write_char(&mut self, c: char) -> Result<(), Error>

Writes a char into this writer, returning whether the write succeeded.

A single char may be encoded as more than one byte. This method can only succeed if the entire byte sequence was successfully written, and this method will not return until all data has been written or an error occurs.

§Errors

This function will return an instance of Error on error.

§Examples

use rune::alloc::fmt::TryWrite;
use rune::alloc::{String, Error};

fn writer<W: TryWrite>(f: &mut W, c: char) -> Result<(), Error> {
    f.try_write_char(c)
}

let mut buf = String::new();
writer(&mut buf, 'a')?;
writer(&mut buf, 'b')?;
assert_eq!(&buf, "ab");