I know "Persistent script states" is in WorkInProgress.
To see this, saving state of reference type variables is difficult. Are Saving call stack and Saving primitive type variables also difficult?
If they are easy, I want to add this ability to AngelScript.

I'm planning to use AngelScript in novel game.
Main script is originally written in xml, and converted to the c-style code by my program, which AngelScript can compile.
Functions in converted code doesn't have any parameters. Only primitive type variable is used as local variable in functions.

Actually, saving the state of reference types is not that difficult, as AngelScript knows the type of the objects on the stack, e.g. due to exception handling. To serialize the reference type the object has to have a special method for serialization that AngelScript can call.

Restricting the serialization to just the primitive types would make it slightly easier, but it would still be a quite complex task.