rust-smallvec

rust-smallvec

[!WARNING] smallvec v2 is on pre-release

this means that there might be unexpected changes between versions. see the changelog for detailed breakdowns

changes include, but are not limited to:

• breaking API changes
• deprecation of items
• adding, removing or modifying features

beware that this is a pre-release and we can't ensure that there are no vulnerabilities or corner cases. if this feels like a substantial risk to you, please downgrade to the latest v1 version

we are looking for people to test this v2 version, so feel free to play around with smallvec and use it for your purposes if this warning is not a concern, and please file an issue on the repo if you find some unexpected behavior or have a request for a feature

Release notes

Small vectors in various sizes. These store a certain number of elements inline, and fall back to the heap for larger allocations. This can be a useful optimization for improving cache locality and reducing allocator traffic for workloads that fit within the inline buffer.

Example

use smallvec::SmallVec;

// This SmallVec can hold up to 4 items on the stack:
let mut v: SmallVec<i32, 4> = SmallVec::from([1, 2, 3, 4]);

// It will automatically move its contents to the heap if
// contains more than four items:
v.push(5);

// SmallVec points to a slice, so you can use normal slice
// indexing and other methods to access its contents:
v[0] = v[1] + v[2];
v.sort();

Feature List

By default, SmallVec does not make use of any feature. SmallVec without any features enabled does not make use of the standard library.

• arbitrary: implements Arbitrary for any SmallVec storing elements that implement Arbitrary
• borsh: implements BorshSerialize, BorshDeserialize and BorshSchema
• bytes: implements BufMut for SmallVec
• defmt: implements defmt::Format for SmallVec
• encase: implements encasing as a runtime-sized array
• internals: exports through the public API TaggedLen and RawSmallVec
• malloc_size_of: implements MallocSizeOf and MallocShallowSizeOf
• may_dangle (nightly): enables the eyepatch optimization for dropping
• rayon: implements parallel iteration
• serde: implements serde's serialization and deserialization
• specialization (nightly): enables specialization, improving performance on some cases
• std: implements the std::io::Write type for SmallVec<u8, N>

The rayon feature implicitly requires std.