Hacker News Reader

Comment by jdougan | Hacker News Reader

As I said in another forum earlier this week,

"A lot of the hate centered around how it wasn’t a systems programming language, when it wasn’t supposed to be one. It’s like complaining your driving instructor’s car can’t be used to dig a trench without extensive modification."

After BASIC, I learned on Pascal (Apple and IBM). It was invaluable to clarify in my mind how programming structures work, as opposed to the (fun) chaos of early BASICs. I really didn't need much more than the I/O available in standard Pascal at the time. And it hid details like endianness that I was not yet ready to handle.

Were there problems? Of course. Among others, the vendors should have done a lot more to standardize extensions, the P1 parameterized array bounds should have been in the initial spec, and while the P-machines had many virtues, performance was not one of them. Far too many of the early implementations just ran the P-code in an interpreter.

View on HN

While there may be general agreement that Pascal is a great teaching language and a weak systems language, I believe that early versions of mac operating system (system N, not OSX) relied heavily on a modified version of Pascal. Perhaps Steve did not get the memo.

Becaues Clascal/Object Pascal had an enormous number of non-standard extensions to make it a much more system and apps oriented language than the 1973 version. I believe Bill Atkinson was involved in the decision. Same story with TurboPascal and Delphi.

Walter's complaint is partially that it needed extensions to do anything non-educational on 1973 hardware. This is true, but to me is vaguely non-sensical, as it clearly had not been designed for that and was labelled as such.

It's been well over 40 years since I wrote Wirth Pascal code, but one of the problems was one couldn't write a line without a line ending. That's not an activity confined to system programming!

Sure. But for the output of the tiny calculator class project we did, it just didn't matter.

Yes, Pascal is good for that purpose.

Many of the decisions for Pascal seem aimed for a teaching language as opposed to a production language. For instance, in a production language, optimisation of generated code is worth a longer compile cycle, but in a teaching language (where programs are repeatedly resubmitted until they barely run, and then are never touched again) short* compile cycles are everything and quality of generated code is an afterthought.

* and cheap: I remember in the days of 30 engineers sharing a VAX that if one person was compiling at a time everything was snappy, but (especially near the end of quarters!) if ten people tried compiling at once interactive latency suffered greatly. Classroom use must've been even worse.

Many of the decisions for Pascal seem aimed for a teaching language as opposed to a production language.

Because it was. The fact it could be extended in so many ways to be a production language shows it had 'good bones', but many practical issues, like I/O, were left as an 'excercise to for the student'.

There seems to have been a lot of revisionist history around Wirths passing with people using Pascals limitations as an indictment of his PLT creds, virtually all of which ignore he was an academic working in academic environment on topics that interested him at the virtual beginning of programming on very, very limited machines. It's like calling Watt a hack because he didn't also add a supercharger and emissions control to the steam engine.

Here's what Wirth wrote about it in retrospective, and yes it was explicitly designed as a teaching language with a syntax suitable for a recursive descent one pass compiler http://youtu.be/5RyU50qbvzQ

> For instance, in a production language, optimisation of generated code is worth a longer compile cycle, but in a teaching language (...) short* compile cycles are everything and quality of generated code is an afterthought.

I don't think this is a valid take. It sounds like an attempt to rationalize away awful build times from some systems language. C++ has atrocious build times, but in contrast C compiles almost instantly. Other production languages such as C# and Java also have fast build times.

I don't think long build times are correlated with optimization or production-ready code. They are however linked with attempts to get compilers to do a lot of work just to get our code to generate machine code, but some of that work is due to how some aspects of a programming language sucks and require more work just to pull off an optimization.

> but in contrast C compiles almost instantly

was that the case 30 years ago?

For some compilers, yes.

Also, code was a lot shorter in those days.

Haha, so true! The Caltech PDP-10 slowed to an agonizing crawl the week before finals. Even though playing games on it was banned for that week.

Original Pascal was a teaching language. That's all.

Are you saying that Pascal dialect had WriteLn but not Write?

No, it has write(), but some versions on some OSs needed an eol to flush the buffers. In general the file ops were deliberately underspecified [1], but it was 1973 and the variety of OSs was much weirder than today.

[1] https://www.standardpascaline.org/The_Programming_Language_P...

> It’s like complaining your driving instructor’s car can’t be used to dig a trench without extensive modification.

Correct. But then you get hired for a trench-digging job, and told that you have to use the car, because reasons. And so you wind up really hating the car, when the problem was the other people who decided that it was the right tool for that job.

> But then you get hired for a trench-digging job, and told that you have to use the car, because reasons.

That's not a problem caused by the car. That's a problem caused by someone looking at a worksheet, see "dig a trench" in it, and promptly say "this looks like a job for my trusty car.".

> It’s like complaining your driving instructor’s car can’t be used to dig a trench without extensive modification.

It's more the other way around: learning to drive on a trench digger. Then you find out that what you really need on the places people actually drive, like a freeway, is a car.

Agreed. Pascal made it simple to understand fast and I was in productive flow.

Then suddenly I realized there are stuff I cannot do with it. That was the last day I used Pascal - and I remember it like my dearest experience in programming!

Reply on news.ycombinator.com