There's a blog post here
Collapse OS — Why Forth?

which links to a long conversation on a ticket here

which tells the story of one person's journey from hearing about Forth to trying it to adopting it for their major project, being Collapse OS, a ground-up operating system. (Previously being written in assembler.)

(I would highly recommend we stick to the Forth aspects of this, not the futurology behind the project, as that is very off-topic. As for the Z80 aspect, I think that's incidental.)



The main advantages given in the blog post for adopting Forth are

compactness
a culture of simplicity
portability

I took the time to read the linked pages, mainly because of my long-standing interest in operating system design. This is not a critique, just some out-loud thinking.


Yes, Forth can appear to be very compact—if one chooses to ignore all the stuff behind the curtain that makes Forth work. I suspect one will find Forth's overall footprint is larger than an equivalent that was efficiently written entirely in assembly language. With any interpreted language, the overhead stays relatively constant, even with the smallest programs. With assembly language, the only overhead is that which the programmer chooses to include in the source code.


That's all a matter of opinion. Forth enthusiasts see Forth as simple. Much of the computing universe sees Forth as an arcane melánge of disjointed words, symbols and reverse Polish gibberish. I'm part of the latter group, and view assembly language as much less impenetrable and more logical than Forth.

On the other hand, if one considers the rapidity at which a Forth program can be written by someone fluent in the language, I suppose there is simplicity over the process of edit/assemble/link/execute. However, that is the case for most interpreted languages.


No operating system is truly portable, especially in the 8-bit microcomputer world. There are always system dependencies that have to be resolved and almost always, they have to be resolved with system-specific assembly language. As Forth cannot execute in a vacuum and must ultimately interact with the underlying hardware, the Forth kernel has to be written for the particular machine architecture on which it is expected to run, which makes it non-portable.

My takeaway is the author of Collapse OS is probably not an expert Z80 assembly language programmer, which would explain why he decided to rewrite it in Forth—there's no question writing an OS in pure assembly language is a daunting task. Also, he notes in his writeup he is a Python developer, which suggests he is likely more comfortable with languages that insulate the programmer from the bare metal (which is a paradox of sorts, considering that at some point an operating system has to be in contact with device registers, etc.). However, he clearly understands the performance implications of writing an OS in Forth, as well as possible maintenance issues related to the language's syntax and structure (this latter item is likely a reason why Forth has not enjoyed much popularity in the general programming community).

BTW, the individual who wrote Collapse OS is a "prepper," which explains the software's name.

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

> I would highly recommend we stick to the Forth aspects of this

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

I did.

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

Sorry, I made a mistake, I expressed my intent too tersely for it to be useful. My aim was to forestall any discussion of the person behind this adventure, or their reasons for undertaking it, because that's solidly off-topic and isn't what interesting (to me, here on this forum) about the story.

For me, the interesting and on-topic aspects of the story are
- what might initially not appeal to a person when first encountering Forth
- what about Forth might eventually win them over
- how they might express themselves having become a convert to Forth

Other potentially interesting and on-topic aspects might be
- how to use this story to bring people on board
- how the conversion of this particular OS from assembly to Forth might go
- how Forth can be taught or learnt

The rather long conversation in the Github issue shows how a person's opinion can change over the course of some space of time, when the conversation remains supportive and addresses a person's present state of mind at each point.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?