!7

cmodule PhilosophyBot2 extends DynPrintLog {

  transient L unmappedLines = ll("good", "early morning");

  transient L unmappedQuestions = ll("what is the time", "how do you feel");

  transient SS mappings = ciMap();

  transient S program = [[

    start

    start => proc {

      run (proc {

        while (there are unmapped questions):

          find (an unmapped question) x

          find (an unmapped line) y

          map x to y

      }
) with backtracking

    }

  ]];

  transient new PhilosophyBot1 bot;

  start-thread {

    bot.program = program;

    bot.addNativePredicate("there are unmapped questions",

      () -> nempty(unmappedQuestions));

    bot.addNativePredicate("find (an unmapped question) x",

      () -> {

        print("find unmapped question x");

        if (empty(unmappedQuestions)) false;

        Iterator<S> it = shuffledIterator(cloneList(unmappedQuestions));

        IF0<O> alternative = new IF0<O> {

          public O get() {

            if (!it.hasNext()) false;

            ret bot.withAlternative(this, litcimap(x := it.next()));

          }

        };

        ret alternative!;

      });

    bot.addNativePredicate("find (an unmapped line) z",

      () -> {

        print("find unmapped line z");

        if (empty(unmappedLines)) false;

        Iterator<S> it = shuffledIterator(cloneList(unmappedLines));

        IF0<O> alternative = new IF0<O> {

          public O get() {

            if (!it.hasNext()) false;

            ret bot.withAlternative(this, litcimap(z := it.next()));

          }

        };

        ret alternative!;

      });

    bot.addNativePredicate("map x to y",

      (SS map) -> {

        S x = map.get("x"), y = map.get("y");

        unmappedQuestions.remove(x);

        unmappedLines.remove(y);

        print("Remaining unmapped questions: " + l(unmappedQuestions));

        mappings.put(x, y);

        print("Mapped question " + quote(x) + " to answer " + quote(y));

        ret bot.withAlternative(() -> {

          print("Undoing mapping of " + quote(x) + " to answer " + quote(y));

          unmappedQuestions.add(x);

          unmappedLines.add(y);

          false;

        }, true);

      });

   bot.onProcedureEnded.add(voidfunc(O proc, PhilosophyBot1.Path path) {

     print("A procedure ended after " + nSteps(path.steps) + ": " + path);

   });

   bot.addNativePredicate("run x with backtracking",

     (SS map) -> {

        S x = map.get("x");

        print("Run x with backtracking: " + x);

        new PhilosophyBot1.Path path;

        bot.runParsedProcedure(bot.parseProcedure(x), path);

        print("Ran x with backtracking: " + x);

        while licensed {

          if (!path.valid) ret true with print("Path not valid anymore");

          print("Have " + nSteps(path.steps));

          if (empty(path.steps)) ret true with print("Path is empty, nothing to backtrack");

          PhilosophyBot1.Step step = last(path.steps);

          print("Backtracking last step: " + step);

          O result = step.alternative();

          print("  Result: " + result);

          if (isFalse(result)) {

            print("Discarding last step as it is done");

            popLast(path.steps);

          }

        }

        true;

     });

   bot.run();

  }

}