// e.g."if a snippet contains token X, it also contains token Y";
// returns an iterator of NLA blocks (one for each possible mapping)
static ItIt<S> ai_pronounResolvedToNLA(S s) {
  AI_PronounResolver1 resolver = new(s);
  resolver.run();
  print("nounPhrases", resolver.nounPhrases);
  print("pronouns", resolver.pronouns);
  
  // mapping: pronoun -> noun phrase
  ret mapI(resolver.allMappings(), mapping -> {
    L<ParsedWithTokens> pwt = replaceElementsUsingMap(resolver.pwt, (Map) mapping);
    pnl(pwt);
    CountingVarMaker varMaker = new("entity");
    new LS lines;
    new Map<ParsedWithTokens, S> entityNames;
    for (ParsedWithTokens p : values(mapping)) {
      S name = varMaker!;
      entityNames.put(p, name);
      //lines.add("there is " + getVar_rec(p) + " " + name);
      lines.add("there is " + name);
      lines.add(name + " is " + getVar_rec(p));
    }
    S prop = joinMap(pwt, p -> str(or(entityNames.get(p), getVar_rec(p))));
    lines.add(prop);
    ret lines(lines);
  });
}