Comment by kick

Bourne liked ALGOL. A lot. So much that he was one of the few people who wrote their own ALGOL-68 compiler. Using the preprocessor to feel more at home is a pretty good idea in this case.

This wasn't particularly popular to anyone who wasn't, well, Bourne, even at the time. I posted an example here: https://news.ycombinator.com/item?id=22199664