pub trait WriteBytes: AsMut<[u8]> {
// Required method
fn write_exact(&mut self, buf: &[u8]);
// Provided method
fn try_write_exact(&mut self, buf: &[u8]) -> Result<()> { ... }
}Expand description
Write a slice of bytes into a buffer.
Writers can be thought of as mutable cursors that only allow you to seek
forward from the current position. They can be implemented with one method;
write_exact. This forcibly attempts to writer the bytes
to the underlying buffer, and advance the buffer forward such that the next
call to write_exact will commit the bytes directly after
those previously written.
WriteBytes uses AsMut<[u8]> as a supertrait. This means
that a generic writer can obtain its current length or mutably peek at the
underlying bytes without advancing the cursor through write operations.
§Examples
Writing into a slice:
use byteio::WriteBytes;
fn main() -> byteio::Result<()> {
let mut buf = [0; 8];
{
let mut buf = &mut buf[..];
buf.try_write_exact(&[1, 2])?;
assert_eq!(buf.len(), 6);
buf.try_write_exact(&[3, 4, 5, 6, 7])?;
assert_eq!(buf.len(), 1);
buf.try_write_exact(&[8])?;
assert!(buf.is_empty());
}
assert_eq!(buf, [1, 2, 3, 4, 5, 6, 7, 8]);
Ok(())
}Required Methods§
Sourcefn write_exact(&mut self, buf: &[u8])
fn write_exact(&mut self, buf: &[u8])
Forcibly attempts to write the exact slice into the buffer.
§Panics
Panics if there are not enough bytes in self.
Provided Methods§
Sourcefn try_write_exact(&mut self, buf: &[u8]) -> Result<()>
fn try_write_exact(&mut self, buf: &[u8]) -> Result<()>
Attempts to write the exact slice into the buffer.
If there are not enough bytes in self this function will return
Error::EndOfStream.