From: mikew50@aol.com (MikeW50)
Reply-To: mikew50@aol.com (MikeW50)
Newsgroups: comp.sys.apple2.programmer
Subject: Re: new programmer looking for languages
Date: 29 Oct 1996 22:29:22 -0500
Organization: America Online, Inc. (1-800-827-6364)
Message-ID: <556i2i$rir@newsbf02.news.aol.com>
References: <553tnl$8s8@news.emi.com>

In message <553tnl$8s8@news.emi.com>, drsmooth@relex.com (Edhel Iaur)
wrote:

> I've heard of the UCSD compiler...what language is it? Pascal?

Actually, it was several. UCSD developed a nice compromise between a
native code compiler and the limited RAM available on early machines, plus
they solved the nagging portability problems that plagued those early days
of computing. The did this by developing an abstract machine that used
instructions taylored to the way compilers work, rather than the way chips
are built. This ideal compiler assembly language was called p-code, mostly
because the flagship language is Pascal. On each target machine, all they
had to do was implement a p-code interpreter in assembly language, and the
operating system and all the compilers worked right away.

Incidentally, this popular idea caught on. Actual chips were built that
executed the ideal code. And if you think that old ideas die away, take a
look at this months cover of Byte Magazine, and ask yourself ehat a "JAVA
chip" might be.  :)

Like UNIX and C, UCSD has always been closely associated with Pascal
because the operating system was written in that language. It's not the
only language they implemented, though. I know for certain that Fortran,
Cobol, PILOT, and Modula-2 have all been implemented on the Apple II for
the UCSD p-system.

Apple Pascal, which is the Apple labeled version of UCSD Pascal, is still
available from Byte Works. As far as I know, none of the other languages
are--but you may be able to pick up copies by posting "wanted to buy"
messages.

Mike Westerfield