[][src]Crate smallvec

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.

no_std support

By default, smallvec depends on libstd. However, it can be configured to use the unstable liballoc API instead, for use on platforms that have liballoc but not libstd. This configuration is currently unstable and is not guaranteed to work on all versions of Rust.

To depend on smallvec without libstd, use default-features = false in the smallvec section of Cargo.toml to disable its "std" feature.

union feature

When the union feature is enabled smallvec will track its state (inline or spilled) without the use of an enum tag, reducing the size of the smallvec by one machine word. This means that there is potentially no space overhead compared to Vec. Note that smallvec can still be larger than Vec if the inline buffer is larger than two machine words.

To use this feature add features = ["union"] in the smallvec section of Cargo.toml. Note that this feature requires a nightly compiler (for now).



Creates a SmallVec containing the arguments.



An iterator that removes the items from a SmallVec and yields them by value.


An iterator that consumes a SmallVec and yields its items by value.


A Vec-like container that can store a small number of elements inline.



Types that can be used as the backing store for a SmallVec


Trait to be implemented by a collection that can be extended from a slice


Common operations implemented by both Vec and SmallVec.



Hint to the optimizer that any code path which calls this function is statically unreachable and can be removed.