If an array is append-only and guarantees that all the existing data is immutable, then we may share the slices of this array safely across threads while the owner can still safely append new data to it.

It's safe because no mutable byte has more than one owner.

When there is not enough capacity for new append, AppendOnlyBytes will not deallocate the old memory if there is ByteSlice referring to it.

Example

rust let mut bytes = AppendOnlyBytes::new(); bytes.push_slice(&[1, 2, 3]); let slice: BytesSlice = bytes.slice(1..); bytes.push_slice(&[4, 5, 6]); assert_eq!(&*slice, &[2, 3]); assert_eq!(bytes.as_bytes(), &[1, 2, 3, 4, 5, 6])