I took his Programming Languages and Translators class when he was at Columbia. It was, hands-down, the best class I've ever taken. His enthusiasm for the sub

I took his Programming Languages and Translators class when he was at Columbia. It was, hands-down, the best class I've ever taken. His enthusiasm for the subject was evident. The aspect about the class I liked best, and which I try to emulate, it that he rarely ever directly answered a question. He would, with incredible patience, ask you questions in-turn to help lead you to the solution or definition. I always found that impressive from a graduate-level professor. I think I still have his ML implementation of Red-Black trees he gave the class.