@@ -190,5 +190,33 @@ describe RubyProlog do end + + it 'should solve the Towers of Hanoi problem.' do + c = RubyProlog::Core.new + c.instance_eval do + + move[0,:X,:Y,:Z] <<= :CUT # There are no more moves left + move[:N,:A,:B,:C] <<= [ + is(:M,:N){|n| n - 1}, # reads as "M IS N - 1" + move[:M,:A,:C,:B], + # write_info[:A,:B], + move[:M,:C,:B,:A] + ] + write_info[:X,:Y] <<= [ + # write["move a disc from the "], + # write[:X], write[" pole to the "], + # write[:Y], writenl[" pole "] + ] + + hanoi[:N] <<= move[:N,"left","right","center"] + query(hanoi[5]).length.should == 1 + + # do_stuff[:STUFF].calls{|env| print env[:STUFF]; true} + + end + + end + + end spec/ruby-prolog_spec.rb b102f80868a1664b0f02755e1c553af4e1f55459 Preston Lee preston.lee@openrain.com http://github.com/preston/ruby-prolog/commit/139398ec4ee499be9b4510c4731b95e1deb4038a 139398ec4ee499be9b4510c4731b95e1deb4038a 2009-02-09T15:13:01-08:00 2009-02-09T15:13:01-08:00 fixing bug in "is" handling cc8465fffb00a58fc742c06d161510e19d125434 Preston Lee preston.lee@openrain.com