Teaching Kids Forth

1 day ago (gracefulliberty.com)

Assuming you’re teaching programming and not “coding”, forth is a fantastic language to teach.

First it’s easy to understand. Second, it’s completely unopinionated, and you can take it anywhere you want to. To write a program in forth is to create a domain specific language for solving that problem.

Forth embodies functional as well as procedural programming, is a high level class language (not Assembler) yet also if you understand forth, you will pick up assembler very easily. (Unlike, say, JavaScript)

It sits precisely in the sweet spot of a central set off paradigms that, once understood, form a bridge to every kind of computer programming, as well as to a whole bunch of data abstractions at a low level.

It might even be the -only- language that people who will learn to program using AI would have to learn, as long as they went deep. At that point they could conceptually work with high level descriptions of what they intended for the coding agent to create, without having the underpinnings be completely opaque, regardless of the actual language used.

  • What is the difference between programming and coding? In my mind they're synonymous.

    • It’s not really a completely clear distinction, but if I was going to try to describe it:

      Coding is writing code to solve a problem. Someone can “know how to code” in one language, and have a very hard time moving away from that language because they understand the symbols more than the ideas.

      Programming is approaching a problem space as a system specification problem and solving it with an algorithmic solution, and it doesn’t matter what language you use because you are approaching it from the symantic direction rather than the syntactic one.

      You are a programmer when all languages are roughly similar to you, even though you may be much more familiar with the syntax of one than you are with others.

      You are a coder when you can write programs, maybe even complicated ones, but you think of the solution in terms of a computer language rather than data structures, transformations, and state machines.

      Most people start as coders, unless they come from a computer science background, or start out in assembly or with a little extra push, languages like forth. If you keep going and start to branch out a bit, most people will become programmers to one degree or another within a few years of working or playing in the field.

      In short and to overgeneralise to the extreme, the focus is on the code vs the data.

      You can also be so far in to the theoretical side that you are a data scientist or mathematician and a coder, but not really a programmer, even though you are solving complex data and algorithmic problems by programming a computer…. So it’s kinda nuanced? I think maybe it’s a matter of how you think about practical computation? But there’s definitely a difference in the depth of knowledge that crosses some kind of inflection point that is non-linear.

    • In my mind, programming is the concepts, especially around problem solving with code as a tool, where coding is specific syntax/implementation, a means to an end. Related, you don't get paid to code, you get paid to program.

  • yeah kids hate syntax

    • Also pretty sure that kids won’t ever have to deal with syntax lol. For better or for worse, Human language is the new programming language, it’s just a specialised dialect and field. I do worry that by teaching coding and not programming we are shooting kids in the foot though. You need to ba able to leverage deep insight to lead coding agent swarms to create actually good codebases.

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    • lol. Forth is pretty syntax sparse, depending on the implementation. Postfix operators solve a lot of that.

Leo Brodie's "Starting Forth: An Introduction to the Forth Language and Operating System for Beginners and Professionals" is well-suited for any level student. It's quite fun and made a mark on my thinking. It's hard for a postfix dereference operator not to.

I really love Forth and spend almost all my free programming time playing with it and I'd never teach it to a class of kids.

  • Yeah Forth doesn't seem very good as a teaching language. Maybe the "first lesson" part where you're just showing how you can build a toy program from simple words would go well, but any nontrivial project where you have to start incorporating DUP and OVER and ROT and PICK and friends seems like a nightmare to teach to anyone who hasn't programmed before.

    • > start incorporating DUP and OVER and ROT and PICK and friends

      If one understands adding and consuming values at the top of the stack, putting the stack in the state you want it is certainly a small logical step without new theoretical baggage.

      Word definitions and the accompanying pointer tricks are more likely to be challenging.

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  • My kid was curious about my HP-35 and I taught them how it works. They got it in no time and I made it an exercise to rewrite math expressions in RPN.

    Not sure they are that interested in programming, but FORTH is a little sweet language.

    My first experience with it was Paul Lutus’ GraFORTH. On the Apple II it was ridiculously fast.

    • lutus also created arachnophilia and sailed or is sailing around the world.

      n coined the term careware. iirc.

      first-hand info. i had downloaded n used arachnophilia.

      he is on hn.

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  • Kids need an antidote to the brain damage that is standard mathematical notation. I prefer lisps variadic prefix notation, but if you're just doing fixed arity functions without higher order functions than prefix and post fix are as good as each other, and you don't have the dreaded sea of parenthesis.

I doubly enjoyed reading this because I feel like I'm reasonably sure the author never ran this through an LLM because of the "cirriculum" typo.

  • This is exactly the kind of spelling mistake ChatGPT makes if you ask it to make spelling mistakes to make text look more authentic.

    What seems to happen is it will get a lot of words like curriculum wrong that people rarely spell incorrectly because they're long enough that if your English isn't confident you would look it up or use a spell checker, or spell words incorrectly that people don't usually spell wrong like 'imediate' or 'puzzel'.

From personal experience, I strongly disagree with the negative comments saying Forth isn't suitable for teaching children.

"Starting Forth" by Leo Brodie was the first programming book I ever read when I was about 6 or 7 years old, after my dad brought it home from work (where they used Forth). To me, the language felt very intuitive and easy to grasp. And Brodie's illustrations helped a lot with visualizing how it all worked.

I used Forth to explain numbers in different radices to my grandson. Being able to interactively try things at the console was really helpful. It also helps to separate the internal number in the machine from how we display it, due to the different operators to print numbers as signed or unsigned. This is something that I have seen young programmers confuse.

I think another area where Forth can help young people is in understanding some low level details like memory addresses and reading and writing memory. It seems simpler than abstracting it to "pointers", more like assembler but interactive.

  • Wouldn't something like Python be better for interactivity?

    • Forth is very good in this regard, because the word names are short and there is no "fluff" around the syntax if you can even call it syntax. Also there is no need to name your data. Literal numbers can be used just as easily even for memory addresses.

      However there is no safety net. ;-)

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Writing RPL on my HP48 as a young teenager influenced the way I thought about programming significantly. RPL IMO is underrated as an educational tool. It introduces the stack based concept, but also the "everything is an object" concept. As a useful language I'm not sure, but it was definitely fun to think about.

OP is speedrunning how to make kids hate programming.

This language is simple unintuitive and the Polish math notation will cause even more confusion.

>> Overall, I don't believe the programming language matters all too much.

Delusional. There is a reason why 99.99% of large projects are done in imperative languages.

I like programming a lot but if my programming journey were started by this teacher and might just became a chef instead.

This seems to be a "do novel things for novelty sake" thing.

Kids need to see the practical applications in the simples and most intuitive way of the things they are learning.

Forth or similar languages are not it.

Even in university level students these languages are both confusing and unintuitive and slow to develop in compared to imperative languages.

  • I don't know.

    It's got some extremely simple rules. 1 data structure. And nothing is particularly hidden.

    Python might be better for actually producing something, but from a 'teaching how computers work' pov, forth would seem to have it's merits. Python hides a lot of stuff, thus we have a situation where people think compilers and interpreters are magical things. If you don't care how the computer works, that's fine, but personally I'd like to teach my kid how a computer works, not how to use some programming language.

    • >> but personally I'd like to teach my kid how a computer works, not how to use some programming language.

      I wonder if assembly is a better choice... hmmm...

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> I wanted to avoid teaching syntax. While Python makes sense as pseudocode [...] it is still nearly incomprehensible to new learners [...] I decided I wanted to either teach Forth or Haskell.

Sorry but this reads like a joke. If you find python incomprehensible, Forth and Haskell won't even register as languages.

  • I think that's because Haskell doesn't need to be understood as a language beyond the fact that it works like maths functions.

    Procedures are a lot harder to explain the first time to people who work with maths functions, especially if you call procedures functions.

Why not Processing or P5.js?

  • did you read the post? it doesn't mention those by name but the reasons it gives for not teaching other languages/tools apply to those too

    • Yes, of course. I just wanted to say that I think these tools are very suitable for teaching programming to beginners in a very short time and with excellent feedback. There's no need to go to the margins.

All things considered, unfortunately, we are better off teaching them plumbing or painting ...

  • Or just concentrate on reading writing and 'rithmetic and let them find a career they want that isn't forced on them