Expand description

A crate for things that are

  1. Lazily initialized
  2. Expensive to create
  3. Immutable after creation
  4. Used on multiple threads

Lazy<T> is better than Mutex<Option<T>> because after creation accessing T does not require any locking, just a single boolean load with Ordering::Acquire (which on x86 is just a compiler barrier, not an actual memory barrier).


Lazy<T> is a lazily initialized synchronized holder type. You can think of it as a LazyTransform where the initial type doesn’t exist.

LazyTransform<T, U> is a synchronized holder type, that holds a value of type T until it is lazily converted into a value of type U.