svoid philosophyBot_collectAndDelete(PhilosophyBot1 bot) {
  bot.addNativePredicate("!collectAndDelete $x $phrase",
    map -> {
      S var = $x(map), phrase = map.get("$phrase");
      LPair<S, SS> l = bot.matchFacts2(phrase);
      bot.deleteFacts(pairsA(l));
      ret map(l, p -> p.b.get(var));
    });
}