Transactions!

0.26

New Features

• Transactions! You may now call Tree::transaction and
  perform reads, writes, and deletes within a provided
  closure with a TransactionalTree argument. This
  closure may be called multiple times if the transaction
  encounters a concurrent update in the process of its
  execution. Transactions may also be used on tuples of
  Tree objects, where the closure will then be
  parameterized on TransactionalTree instances providing
  access to each of the provided Tree instances. This
  allows you to atomically read and modify multiple
  Tree instances in a single atomic operation.
  These transactions are serializable, fully ACID,
  and optimistic.
• Tree::apply_batch allows you to apply a Batch
• TransactionalTree::apply_batch allow you to
  apply a Batch from within a transaction.

Breaking Changes

• Tree::batch has been removed. Now you can directly
  create a Batch with Batch::default() and then apply
  it to a Tree with Tree::apply_batch or during a
  transaction using TransactionalTree::apply_batch.
  This facilitates multi-Tree batches via transactions.
• Event::Merge has been removed, and Tree::merge will
  now send a complete Event::Set item to be distributed
  to all listening subscribers.