Optional *is going to* be made a value type. However, unlike the binary choice of class/value type, project valhalla will provide a more granular approach, com

Optional *is going to* be made a value type. However, unlike the binary choice of class/value type, project valhalla will provide a more granular approach, coming with incremental performance benefits and constraints. In the current spec draft, the type system boils down to 4 categories: - Fully mutable, polymorph classes - Immutable, monomorphic classes - Immutable, monomorphic classes + null-hostile - Immutable, monomorphic classes + null-hostile + multithreading-unsafe Another story for nullability is being investigated as well which would allow for full performance gain as well as full backwards compatibility.