svoid gazelle_addPredictionToTreeNode(GazelleTree child, O... _) {
  bool debug = boolPar debug(_);
  Set<S> badComments = cast optPar badComments(_);
  Set<S> acceptablePurposes = cast optPar acceptablePurposes(_);
  
  RuleEngine2_MatchedRule r = child.mr;
  GazelleEvalContext ctx = child.ctx;
  
  if (containsAny(r.rule.comments, badComments)
    || acceptablePurposes != null && !acceptablePurposes.contains(unnull(r.rule.purpose))) {
    if (debug) print("prediction=bad for various reasons");
    child.prediction = 'bad;
  } else {
    /*ai_gazelle_analyzeStatementsForRule_Data data = ctx.dataByRule.get(r.rule.globalID);
    child.prediction = data == null ? null : ai_gazelle_predictor1_onData(r, data);*/
    if (ctx.predictor == null)
      child.prediction = null;
    else {
      child.prediction = ctx.predictor.get(ctx, r);
      if (debug) print("Prediction=" + child.prediction + " for " + r + " (" + (r.moreConditions() ? "unsatisfied" : "satisfied") + ") by " + ctx.predictor);
    }
  }
}