Pascal (Turbo/Borland) was the most most fun I had programming back then. The "Unit" of compiliation just worked (and yes it allowed only DAG-like dependency hierarchies). It was super fast to compile and use, but also to edit/debug.

Then something got lost with Delphi, it's not that it was a bad product, but people started looking elsewhere...

I still cherish the day, as Pascal gave me the headstart to C/C++ from Apple Basic, but also allowed me to start using bit of inline assembly and learn it along the way...