4 ms·

The point about Lisp is that, lists aren't just the main data structure: programs themselves are lists. Many years ago, I began developing a language in which

The point about Lisp is that, lists aren't just the main data structure: programs themselves are lists. Many years ago, I began developing a language in which programs are directed graphs (http://fmjlang.co.uk/fmj/FMJ.html http://fmjlang.co.uk/fmj/FMJ.html), and on which I still work when I find the time. One of my aims was to make the language fully homoiconic, like Lisp. The problem I had, and which I've only solved recently, is that directed graphs in mathematics just have vertices and arcs, each of which can be labelled, and that's all, but programs in FMJ have vertices (but with ordered inputs and ordered outputs) and arcs, but also constants and enclosures. So programs are extended directed graphs, and the extensions are only really useful for writing programs. Now I have shown that programs are homeomorphic to directed graphs in the mathematical sense - graphs with just labelled vertices and arcs can be converted to programs and vice-versa. I have also added graph processing primitives, but haven't got much further as I've been busy with other things. I do intend to update my web pages soon, with descriptions of the graph processing and the other features I've added.

nudpiedo 4y ago
After the introduction regarding programs that should be different, etc I expected something innovative but... how is fmjlang different than any lisp? it seems like nothing else than visual polish notation with lisp semantics. Perhaps the "parallel" part is just a different evaluator for a lisp, but I see no other differences to be honest.
- DonaldFisk 4y ago
  FMJ is a statically typed dataflow language. Programs are directed graphs. It has no program counter or stack. There are queues of tagged values at vertex inputs, and vertices execute asynchronously when all their inputs have values with the same tag. Lisp is a dynamically typed impure functional language. Programs are nested lists. Its interpreter runs by calling eval and apply, which call each other. After compilation, code runs on a machine with a program counter and stack. I don't see much similarity myself, and I wrote FMJ and know Lisp well.
  - nudpiedo 4y ago
    I think you should try more lisps. Still good that someone tries to experiment with visual Polish notation, typed or not.

nudpiedo 4y ago

After the introduction regarding programs that should be different, etc I expected something innovative but... how is fmjlang different than any lisp? it seems like nothing else than visual polish notation with lisp semantics. Perhaps the "parallel" part is just a different evaluator for a lisp, but I see no other differences to be honest.

DonaldFisk 4y ago
FMJ is a statically typed dataflow language. Programs are directed graphs. It has no program counter or stack. There are queues of tagged values at vertex inputs, and vertices execute asynchronously when all their inputs have values with the same tag. Lisp is a dynamically typed impure functional language. Programs are nested lists. Its interpreter runs by calling eval and apply, which call each other. After compilation, code runs on a machine with a program counter and stack. I don't see much similarity myself, and I wrote FMJ and know Lisp well.
- nudpiedo 4y ago
  I think you should try more lisps. Still good that someone tries to experiment with visual Polish notation, typed or not.