#vec #reuse #allocation #api #zero-alloc

vec_storage_reuse

Provides an API to reuse a Vec’s allocation

1 unstable release

0.1.0 Sep 4, 2022

#23 in #reuse

LGPL-3.0-only

8KB
63 lines

vec_storage_reuse

Crates.io License

Provides an API to reuse a Vec's allocation.

This is useful to achieve zero-alloc when storing data with short lifetimes in a Vec:

    let mut objects_storage: VecStorageForReuse<Object<'static>> = VecStorageForReuse::new();

    while let Some(byte_chunk) = stream.next() { // byte_chunk only lives this scope
        let mut objects: &mut Vec<Object<'_>> = &mut *objects_storage.reuse_allocation();

        // Zero-copy parsing; Object has references to chunk
        deserialize(byte_chunk, &mut objects)?;
        process(&objects)?;
    } // byte_chunk lifetime ends

Credits:

This crate delegates the actual unsafe functionality to the recycle_vec crate, and just provides an interface that abstracts the swapping with the container through Drop, so that one can never forget to swap back the temporary object with the storage

Dependencies

~9KB