His solution is the "problem" of having to update the whole game state in a function is "is not to return new versions of anything, but to simply return stateme

His solution is the "problem" of having to update the whole game state in a function is "is not to return new versions of anything, but to simply return statements about what happened" and "Actually handling what happened is a separate step, one that can be done later on in the frame." Did he just make an imperative DSL out of erlang?