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1 point by rincewind 4523 days ago | link | parent

The Problem with unification and logical variables would be that they have to be dynamic in scope and work with a call-by-name evaluation strategy, at least in Prolog.

Anyway, you could build a Prolog-Like DSL with pat-m and amb

  http://arclanguage.org/item?id=2556
  http://arclanguage.org/item?id=6669
While logic Programming in Arc can make problem-solving easier, i think it introduces problems for libraries:

- How should you call functional functions from logical functions?

- How should you call logical functions from functional functions without violating referential transparency?

- Do closures over logical variables make any sense?

- Should goals be limited in scope? Lexical or dynamic? If I call 2 logical functions from different modules I may or may not want the first to be retried when the second fails, depending on the context.