svoid test_ai_ruleOfThree_3() { 
  test_ai_ruleOfThree_3(null);
}

svoid test_ai_ruleOfThree_3(IF2<S> f) {
  S db = [[
    Solar Powered Air Conditioner! => an air conditioner powered by solar
    pedal powered air conditioner => an air conditioner powered by pedal
    gravity powered machine => a machine powered by gravity
  ]];
  L<BasicLogicRule<S>> l = parseLogicRules_tlft(db);
  for (BasicLogicRule<S> r : l)
    testFunctionValues_twoArgs(f, pair(first(tlft(db)), r.lhs), r.rhs);
}