Crate pvec

Persistent vectors with efficient clone, append and split operations with idiomatic Rust interface.

Provided vector types

There are three public vector types available at pvec-rs:

• RbVec: based on RbTree with naive append and split operations. This type is not recommended for use, as it is here solely for comparison in benchmarks.
• RrbVec: based on RrbTree that enables efficient append and split operations.
• PVec: a persistent vector that starts out as the standard vec, and transitions to RrbVec on the first clone. The cost of its operations is identical to the representation it is backed by.

All vector types in the list expose exactly the same set of operations with identical API. The difference is only in the cost of operations.

Features

RbVec and RrbVec both use Rc for garbage collection. The library provides an option to compile all vectors using Arc if needed, especially when passing instances between threads. To compile the library with Arc, use the arc feature flag.

All types implement Rayon’s IntoParallelIterator trait, that enables the conversion into a parallel iterator. As dependency on Rayon is optional, you will need to explicitly request the parallel iterator implementation by passing both the arc and rayon_iter feature flags.

By default, the tree-based vectors have nodes that are 32 elements wide. The maximum number of child nodes is also referred to as the branching factor. This value can be changed to 4 if necessary, by specifying the small_branch feature flag. Though, the default value of 32 is recommended for optimal performance.

Modules

• core
  A module providing persistent vector types based on RrbTree.
• iter
  A module providing implementation of the standard Iterator, as well as Rayon’s ParallelIterator if the rayon_iter feature flag is specified.

Structs

• PVec
  A persistent vector that is backed by the flat representation - the standard vector, or the tree-based vector when cloned.