On Thu, May 9, 2024 at 6:31 PM Paul Koning via cctalk <cctalk@classiccmp.org> wrote: > > On May 9, 2024, at 6:43 PM, Chuck Guzis via cctalk <cctalk@classiccmp.org> > > wrote: > > ... > > I've written code in Pascal, as well as Modula-2. Never liked > > it--seemed to be a bit awkward for the low-level stuff that I was doing. > > Not surprising, since that's not what it is all about. Both, like their > predecessor ALGOL-60 as well as successors like Ada, are strongly typed > languages where doing unsafe stuff is made very hard.
HP chose Pascal as their system programming language when they came to rewrite the HP 3000's MPE Operating System onto PA-RISC to produce MPE/XL in the mid 80s. It had many extensions to solve the inherent limitations of standard Pascal, like the ability to have formal parameters which could receive actual values of any type, extensive pointer support, well-defined variant records, etc., etc. It remained the most popular language for writing low-level code inside HP and for customers as well, even after C became available. C (including GCC when we got POSIX support) was more commonly used to port open source stuff to the machine. We sold an early client-server retail POS system with a Classic MPE 3000 talking to HP-150 IIs over serial ports, which was written in PASCAL/V on the 3000 and Microsoft Pascal on the HP-150s. Even this earlier Pascal had sufficient extensions to get done what you needed to do without issue.
