Type Alias HistoryBuf 

pub type HistoryBuf<T, const N: usize> = HistoryBufInner<T, HistoryBufStorageInner<[MaybeUninit<T>; N]>>;

A “history buffer”, similar to a write-only ring buffer of fixed length.

This buffer keeps a fixed number of elements. On write, the oldest element is overwritten. Thus, the buffer is useful to keep a history of values with some desired depth, and for example calculate a rolling average.

Examples

use heapless::HistoryBuf;

// Initialize a new buffer with 8 elements.
let mut buf = HistoryBuf::<_, 8>::new();

// Starts with no data
assert_eq!(buf.recent(), None);

buf.write(3);
buf.write(5);
buf.extend(&[4, 4]);

// The most recent written element is a four.
assert_eq!(buf.recent(), Some(&4));

// To access all elements in an unspecified order, use `as_slice()`.
for el in buf.as_slice() {
    println!("{:?}", el);
}

// Now we can prepare an average of all values, which comes out to 4.
let avg = buf.as_slice().iter().sum::<usize>() / buf.len();
assert_eq!(avg, 4);

Aliased Type

pub struct HistoryBuf<T, const N: usize> { /* private fields */ }