Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!bradley
From: bradley@cs.utexas.edu (Bradley L. Richards)
Newsgroups: comp.lang.prolog
Subject: '->' operator
Message-ID: <291@valverde.cs.utexas.edu>
Date: 3 Jan 91 22:26:08 GMT
Organization: Dept of Computer Sciences, UTexas, Austin
Lines: 21

I have a (probably silly) question regarding the '->' operator in Quintus.
Suppose I say

   Condition -> Predicate

If the condition is true, the predicate will execute.  Fine.

If the condition is true and the predicate fails, the whole conditional fails.
  This makes sense since logically (true -> false) is false.

If the condition is true and the predicate is true, the whole thing succeeds.
  This makes sense since (true -> true) is true.

BUT if the conditional is false, the ugly little beastie fails--this doesn't
  make sense since logically (false -> anything) is *true*.

Why is this implemented the way it is?

Thanks,
Bradley
bradley@cs.utexas.edu