Pascal at Apple

So although it doesn't quite make BGI graphics based apps run directly on Windows...it's still quick and easy enough to have some fun. I did it specifically to give myself a way to make programming fun again at a time when I was feeling a bit burned out from working on massive, overly complex C# and JavaScript code all day at the office.

Meanwhile, the Apple ][+ could only display 40 columns on screen, where of course by "screen" I mean "television". (You could buy another big card to give you enough memory to display 80 columns at a time, but who had the cash to make another huge purchase like that?). Of course, 40 columns isn't enough to write in a structured programming language with indentation like Pascal, and in fact the Pascal program itself supported logical lines of up to 80 characters.

This issue was resolved as brilliantly as you might expect. You could toggle between looking at the left half of your program (cut off at the 40-character mark) or the right half. I'm not kidding.

Pascal was designed to allow single pass compilation of programs, while the C preprocessor alone was a source of what was immense overhead at that time. On CP/M, Turbo Pascal blew all C compilers out of the water in terms of compilation speed. The one C compiler I had on a ZX Spectrum at the time did not actually implement the full language so that you'd have some memory left over (I remember that the C type cast syntax was replaced with a keyword in order to simplify the parser, for example).

That said, UCSD-Pascal on an Apple II (which we got to use in school as part of our regular computer science course), was not all that convincing as an implementation (even if the system as a whole was fairly impressive). Because it used a bytecode interpreter (even if that bytecode interpreter leveraged type information and was much faster than a bytecode interpreter for a dynamically typed language), execution speed – including that of the development environment, which was written in UCSD-Pascal itself – was still pretty sluggish in comparison to an actually compiled language. (The UCSD p-code in principle also allowed compilation to native code, but at least the system I had access to – that was in the early 80s – didn't support that.) But it was still more pleasant than many other compilers, and that was at a time when cassette recorders were often still the primary external storage medium, so people were more tolerant, when their point of comparison was systems that literally included source code from cassette tape at compile time, because for large programs you couldn't fit both the source code and the object code into memory at the same time.

When will someone build HN for Audio/Video.