Struct Cursor

pub struct Cursor<T, B: Buffer<T>> { /* private fields */ }

A cursor for safely writing into an uninitialized buffer.

A Cursor is returned from Buffer::cursor, which provides way to write to a Buffer without needing to use unsafe.

Examples

let mut buf = Vec::with_capacity(256);
let mut cursor = Cursor::new(spare_capacity(&mut buf));
let _nread = read(&input, &mut cursor).unwrap();
let _nread = read(&input, &mut cursor).unwrap();
let _nread = read(&input, &mut cursor).unwrap();
let total_read = cursor.finish();

Implementations

impl<T, B: Buffer<T>> Cursor<T, B>

pub const fn new(b: B) -> Self

Construct a new Cursor.

pub fn remaining(&self) -> usize

Return the remaining amount of space in the buffer.

pub fn write(&mut self, t: T)

Write an element to the buffer.

Panics

Panics if this cursor has already reached the end of the buffer.

pub fn write_slice(&mut self, t: &[T])

where T: Copy,

Write multiple elements to the buffer.

Panics

Panics if this cursor is already within t.len() elements of the end of the buffer.

pub fn finish(self) -> B::Output

Finish writing to the buffer and return the output value.

Trait Implementations

impl<T, B: Buffer<T>> Buffer<T> for &mut Cursor<T, B>

type Output = usize

The type of the value returned by functions with Buffer arguments.

fn buffer_ptr(&mut self) -> *mut T

Return a raw mutable pointer to the underlying buffer.

fn buffer_len(&self) -> usize

Return the length in elements of the underlying buffer.

unsafe fn assume_init(self, len: usize) -> Self::Output

Assert that len elements were written to, and provide a return value.

fn cursor(self) -> Cursor<T, Self>

Return a Cursor for safely writing to the buffer.