Prolog/Usergroups

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[edit] Prolog vs Lisp

[1]

Espen Vestre wrote:

      Raffael Mancini <ramanci@xxxxxxxx> writes:
  
          Well not every relation is a function, as relations can have more than
          one results which is not allowed for functions. So functions are a
          subset of relations.
  
  
      You're both missing the point... Heck, I thought this was completely
      obvious to any lisper (but I have to admit that I've probably got a
      minor brain damage due to some exposure to axiomatic set theory and
      lambda calculus)! What do you guys do when you encounter a relation
      and need to implement a check for it? Run for help from the prolog
      guys? I think not! You probably implement a in-my-relation-p
      function. And there's my point: Any relation is also a function, but
      of course a function with a different /range/, namely the set of truth
      values {0, 1} (or {T,F}, (t nil) or whatever notation you like :)).
  
  What I was talking about are strictly mathematical function, but I
  think I got your point.