Mapper type

Signature:

export type Mapper<TContext extends MachineContext, TExpressionEvent extends EventObject, TResult, TEvent extends EventObject> = (args: {
    context: TContext;
    event: TExpressionEvent;
    self: ActorRef<TEvent, MachineSnapshot<TContext, TEvent, ProvidedActor, string, unknown>>;
}) => TResult;

References: MachineContext, EventObject, ActorRef, MachineSnapshot, ProvidedActor