static L<WeightedProduction> ai_buParser_parseWeightedProductions() {
  new L<WeightedProduction> l;
  for (S s : mL(ai_language() + " bottom-up groupings")) {
    L<S> meta = splitAtComma(trailingAngleBracketStuff(s));
    s = dropTrailingAngleBracketStuff(s);
    L<S> tok = javaTokWithAngleBracketsC(s);
    WeightedProduction p = null;
    double weight = 1.0;
    for (S met : meta)
      if (startsWithDigit(met))
        weight = parseDouble(met);
    if (l(tok) == 5)
      p = WeightedProduction(tok.get(0), tok.get(2), tok.get(4), weight);
    else if (l(tok) == 3)
      p = WeightedProduction(tok.get(0), tok.get(2), weight);
      
    if (p != null) {
      for (S met : meta)
        if (eqOneOf(met, "L,", "R", "K"))
          p.simplificationHint = met;
      l.add(p);
    }
  }
  ret l;
}