Nice to see another developer who tried to implement Forth in Go (here’s mine: [0]). It’s not easy and usually takes several iterations.
His implementation, while working for his use cases, is actually quite far from the originals. He uses separate Go structures for words, memory, for-loops, etc. Most of the default Forth implementations of words will fail, since they expect the heap and stack to behave in a certain way. Also, every major word is implemented directly in Go, with no bootstrapping.
> However, it's insufficient for the hacker level, because the host language interpreter (the one in Go) has all the control, so it's impossible to implement IF...THEN in Forth
Well, I did it with a ... heap []any ... data structure. Works well enough.
Thanks for the note. Much of the blog post is dealing with this - how the approach I took for the Go implementation is not sufficient for the hacker level - because the code isn't stored anywhere but remains as text. This isn't a Go issue, it's a result of the specific design decision of how to implement it.
The second implementation - in C - does it the "right way", with both code and data living in the same memory, and thus allows all the usual Forth shenanigans. Again, this has all to do with the design approach and not the implementation language. Nothing precludes one from writing such an implementation in Go :-)
bertili•1h ago
Forth can be beautifully and efficiently implemented in portable c++ using the using continuation passing style via the clang musttail attribute. See Tails [1].
s-macke•1h ago
His implementation, while working for his use cases, is actually quite far from the originals. He uses separate Go structures for words, memory, for-loops, etc. Most of the default Forth implementations of words will fail, since they expect the heap and stack to behave in a certain way. Also, every major word is implemented directly in Go, with no bootstrapping.
> However, it's insufficient for the hacker level, because the host language interpreter (the one in Go) has all the control, so it's impossible to implement IF...THEN in Forth
Well, I did it with a ... heap []any ... data structure. Works well enough.
[0] https://github.com/s-macke/Forthly
eliben•50m ago
The second implementation - in C - does it the "right way", with both code and data living in the same memory, and thus allows all the usual Forth shenanigans. Again, this has all to do with the design approach and not the implementation language. Nothing precludes one from writing such an implementation in Go :-)