Comment by eimrine

5 years ago

Is there any Lisp interpretation on J language? I have hard time searching anything called with one letter only.

4 comments

eimrine

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rscho  5 years ago

Anyways, info about J can pretty much be found only on its website (jsoftware.com), so don't really bother looking elsewhere. The only other good place is Rosettacode.

What do you mean by "Lisp interpretation on J language"?

There's an APL in Common Lisp called April. Otherwise, there's an unfinished J interpreter on the Racket package manager.

  • eimrine  5 years ago

    Sorry for incorrectness, I want to look at interpreter of any dialect of Lisp language, written in J, if the one exists. I found J's approach to syntax interesting to explore.

    • rscho  5 years ago

      Here you are:

      https://code.jsoftware.com/wiki/Scripts/Scheme

      http://tangentstorm.github.io/apljk/bjonas-scheme.ijs.html

      However, in my understanding this code is clear but is just an exercise to use J. A real Scheme parser in J would go through the use of ;: which is a primitive defining a state machine. Given the appropriate state table, it would yield a Scheme tokenizer (with the whole thing amounting to state_table ;: string). Here be dragons, though! You can find a J parser in J (not up to date with current J) using it here:

      https://www.jsoftware.com/help/dictionary/d332.htm

    • kd0amg  5 years ago

      Writing a lisp interpreter in J won't really do more to help explore J's syntax than writing anything else in J. It might be a good way to explore how J handles tree-like data, but that's not really something J is designed to do well (if you really want to use an array-oriented language for tree processing, Aaron Hsu's dissertation covers a range of techniques that are more scalable than the naïve nest-of-short-boxed-vectors approach typically used in J).