Give the desire for lambdas to enable more simple concurrent programming, and the added complexity mutating the external variables in the implementation, I thin

Give the desire for lambdas to enable more simple concurrent programming, and the added complexity mutating the external variables in the implementation, I think they made the right choice. If you _really_ have to mutate those variables then put them into a final array, and alter the entries in that, the same can be used if you need to do an effective pass by reference.