Struct SpareCapacity

pub struct SpareCapacity<'a, T>(/* private fields */);

Available on crate feature alloc only.

A type that implements Buffer by appending to a Vec, up to its capacity.

To use this, use the spare_capacity function.

Because this uses the capacity, and never reallocates, the Vec should have some non-empty spare capacity.

Trait Implementations

impl<'a, T> Buffer<T> for SpareCapacity<'a, T>

type Output = usize

The number of elements written into the buffer.

This is somewhat redundant, as set_len is also called on the referenced Vec, however it can be convenient in some cases, such as for testing for end-of-stream.

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.