I'm also a student of his, and later met him socially on a few occasions as a graduate student (in a different institute).
Undergraduate students were all in awe of him, but I got the impression that he did not particularly enjoy teaching them (Unlike other professors, however, he did not try to delegate that part of his responsibilities to his assistants). He seemed to have a good relationship with his graduate students.
In his class on compiler construction, he seemed more engaged (the students were already a bit more experienced, and he was iterating the Oberon design at the time). I remember an exchange we had at the oral exam — he asked me to solve the "dangling ELSE" problem in Pascal. I proposed resolving the ambiguity through a refinement of the language grammar. He admitted that this would probably work, but thought it excessively complex and wondered where I got that idea, since he definitely had not taught it, so I confessed that I had seen the idea in the "Dragon Book" (sort of the competition to his own textbook). Ultimately, I realized that he just wanted me to change the language to require an explicit END, as he had done in Modula-2 and Oberon.
Socially, he was fun to talk to, had a great store of computer lore, of course. He was also much more tolerant of "heresies" in private than in public, where he came across as somewhat dogmatic. Once, the conversation turned to Perl, which I did not expect him to have anything good to say about. To my surprise, he thought that there was a valid niche for pattern matching / text processing languages (mentioning SNOBOL as an earlier language in this niche).
Undergraduate students were all in awe of him, but I got the impression that he did not particularly enjoy teaching them (Unlike other professors, however, he did not try to delegate that part of his responsibilities to his assistants). He seemed to have a good relationship with his graduate students.
In his class on compiler construction, he seemed more engaged (the students were already a bit more experienced, and he was iterating the Oberon design at the time). I remember an exchange we had at the oral exam — he asked me to solve the "dangling ELSE" problem in Pascal. I proposed resolving the ambiguity through a refinement of the language grammar. He admitted that this would probably work, but thought it excessively complex and wondered where I got that idea, since he definitely had not taught it, so I confessed that I had seen the idea in the "Dragon Book" (sort of the competition to his own textbook). Ultimately, I realized that he just wanted me to change the language to require an explicit END, as he had done in Modula-2 and Oberon.
Socially, he was fun to talk to, had a great store of computer lore, of course. He was also much more tolerant of "heresies" in private than in public, where he came across as somewhat dogmatic. Once, the conversation turned to Perl, which I did not expect him to have anything good to say about. To my surprise, he thought that there was a valid niche for pattern matching / text processing languages (mentioning SNOBOL as an earlier language in this niche).