For anyone who read What's the big deal? and was disappointed that Logical Programming took a backseat to the other three branches of programming, this current question is framed in a very Logical Programming kind of way.

First we list some "Truths" about our world, then we attempt to derive the truthfulness of other relationships, based on the principals of logical reasoning.

The dearth of answers here shows that perl doesn't intuitively behave this way. For logical programming languages, this problem is trivial (could probably be the first example in the intro book), because they are designed to solve exactly this type of problem.

Sorry I didn't address the actual question.... perhaps someting like Prolog is better suited for this. (Though I'm sure some clever person will work some sort of perl solution out...)

-Blake

In reply to Re: Sorting, given only comparisions by blakem
in thread Sorting, given only comparisions by Anonymous Monk

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