They effectively change the structure of your code. Every time you do an operation on a real number, it essentially launches a new process that runs indefinitel

They effectively change the structure of your code. Every time you do an operation on a real number, it essentially launches a new process that runs indefinitely in the background. I would file that under speed problems. To control the speed penalty, you need to make deep changes to your code. I think Andrej Bauer came to this conclusion. Regarding computability, it's not so bad. Basically a continuous operator is usually computable. Example: Integration is continuous, hence (likely, and in this case actually) computable.