What is it about the Think Pascal debugger that makes it so legendary?

Question

I have been sharpening the coding knives and getting back into dev. A few years ago, many people mentioned that the Symantec Think Pascal debugger that came on the (classic) Mac was the absolute bee's knees, and that nothing else was like it anywhere. I found that statement odd, considering that no one has tried to clone said debugger... what was it exactly that made this particular debugger so special ?

Answer 1

Answering this as someone who worked at (pre-Symantec) Think in a minor role while Macintosh Pascal was being developed (1984).

It was revolutionary for two reasons: first, it was an incremental compiler. Getting rid of the edit-compile-link-test cycle is a huge benefit. If you Google Mel Conway (chief scientist at Think), I believe you'll find some notes on the construction of incremental compilers (I looked at his main site before posting and it seems to be under construction).

The second reason was that it was a GUI, when nothing else was, and worked with actual program code. To put this in comparison, I don't believe that symbolic debuggers for MS-DOS or the Mac were available until several years later (I recall one Mac project in 1985/86 where I was constantly interpreting the assembly dumps for the rest of the team), and they're a far cry from source-level debugging. Microsoft released a source-level debugger with Quick C in 1988 (iirc); I never worked with Turbo-Pascal or Turbo-C, so don't know what they had.

Today, pretty much every IDE gives you equal or better debugging features ...