Comment by c2the3rd
5 years ago
Why not say "Every ~~Forth~~ program is its own DSL for accomplishing its work."? For moderately complicated programs in any language you choose, it can take a long time to grok how the literal code relates to solving the conceptual problem. No language can build in every abstraction, and no programmer has time to learn them all.
I think you are close to part of an answer, but it isn't because Forth and Lisp expect one to do more work than other languages. If anything, they expect one to do less. The problem is programmers feel lost because there is no way to differentiate the bedrock of the language from higher abstractions. C has operators and statements and keywords that tell you there is nothing "underneath" what you are looking at. With Forth, everything is words. With Lisp, everything is lists.
To be fair, it is very common for Forth programmers to redefine the interpreter as they go. You literally change the language in your program. That's a very different expectation for other kinds of languages.
> You literally change the language in your program. That's a very different expectation for other kinds of languages.
I wonder about that. A few weeks back I read about a coroutines implementation in C, using plain C and lots of intricate preprocessor definitions:
https://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
There are similar examples in just about any language out there. People use whatever tools the language ecosystem provides to change the language to fit some problems better. Some languages are easier to change and extend, some are harder, but that doesn't stop people from trying to do this anyway.
I think there's a level of familiarity with the language above which changing it is a natural thing to do. It can take years before you learn a "normal" language well enough to be able to do this, but with Forth, Scheme, Prolog, and the like, you're basically required to do this from the get-go. My intuition is that these languages simply target advanced, already experienced programmers, while completely ignoring the beginners. So it's more of the optimization for a different user-base, IMO. That would also explain how these languages are still alive, despite their communities being very small for the last 50 years.