Re: Low-level vs. High-level programming (was My First Computer)

["John B. Matthews" <nospam@nospam.com>]

In article <ShnRa.14919$kI5.9342@nwrddc02.gnilink.net>,
 "Michael Pender" <mpender@hotmail.com> wrote:

> John B. Matthews <nospam@nospam.com> wrote in message
> nospam-967967.21253716072003@clmboh1-nws3.columbus.rr.com">news:nospam-967967.21253716072003@clmboh1-nws3.columbus.rr.com...
> >
> > Logo was a delightful environment, but not the only "serious" recursive
> > stack machine in wide use on Apple II.
> >
> > Apple's UCSD Pascal implemented a very efficient stack machine. Each
> > stack frame had a static and dynamic link to allow recursion from an
> > arbitrary nesting level.
> 
> Apple Pascal was a half-baked implementation of the language that offered
> very limited system access.  It was a compiled Fortran program that
> inherited all of the limitations of the Fortran language, as well as those
> of Pascal. For example, a program could not have more than 3 files open
> at once, system-wide.

Umm, the Fortran compiler was written in Pascal and assembler to 
run under the p-ystem, not the other way around. It was 
copy-protected, slow, buggy and never got updated. Although the 
number of open files was never a serious limitation, the 
primitive disk allocation scheme was prone to fragmentation.

The rest of the system was quite robust: Apple Pascal disk I/O 
was very efficient; it was the forerunner of ProDOS. The 
p-system was used to develop scores of widely used applications, 
including PFS, Jack, VersaForm, QuickFile, Smartcom, Apple 
Business Graphics, Wizardry and the AppleWorks tutorial. The 
UCSD language extensions for strings and separate compilation 
were implemented in scores of subsequent systems for Apple ///, 
Lisa and Macintosh, not to mention Turbo Pascal and Delphi.

To me, the most compelling feature was being able to mix low- 
and high-level code cleanly.
 
> 
>[Forth discussion elided]
> - Mike

BTW, earlier in this thread someone asked about a graphical 
Pascal for educational use. I found an old article that referred 
to it as "Instant Pascal."

John
----
jmatthews at wright dot edu
www dot wright dot edu/~john.matthews/