AT THE Vanguard Computing Center – in Washington, D. C, I watched a young woman present a machine with an extremely complex problem in ballistics involving hundreds of variables. At once lights on a control panel twinkled and winked as the computer checked to see that all equipment was operating properly. Then it set briskly to work. Magnetic tapes spun in their shiny glass-and-steel vacuum cabinets, the high-speed printer muttered. Suddenly the machine stopped and the electric typewriter wrote: “Last entry improperly stated!”

A little embarrassed, the young operator corrected her error, and the machine started again. Four minutes later it gave an answer that had required several million individual calculations.

“This is a wonderful machine” the girl said, “but it makes you shiver sometimes, especially when you give it a wrong figure. Once in a while we give it an incorrect figure on purpose—just to see it sneer at us.”

– THINKING MACHINES ARE GETTING SMARTER (Oct, 1958)

I’d never discourage anyone from making the most fun error messages and interactions possible. But when being sneered at by the machine gives operators more of a connection to it than using it normally, I think something is broken. I can’t imagine that fostering a healthy operator-machine relationship. Honestly though, I don’t know that it’s worse than the same boring regular interactions, but with boring error messages instead.

All languages should include well-written error messages as part of their specification. These messages should include a link to a good explanation of the problem, and anything someone learning the language might want to know, like the design behind the error.

Every standards-compliant compiler would be required to emit the readable error messages.

This could eliminate inscrutable error messages, in one fell swoop.

(The old MPW Compiler had some
quirky and humorous error messages. “This struct already has a perfectly good definition”, for example. Unfortunately, I don’t know of any compiler that had different but more useful error messages. It’s time somebody wrote one.)