svoid ai_parseTree_makeWeights(AI_BottomUpParser1 parser, L<WeightedProduction> productions, final PTElement e) {
  ret ai_parseTree_makeWeights(parser, productions, e, 1, ai_bottomUpParser_maxDepth());
}

svoid ai_parseTree_makeWeights(AI_BottomUpParser1 parser, L<WeightedProduction> productions, final PTElement e, int level, int maxLevel) {
  ping();
  
  if (level >= maxLevel)
    fail("Max parse tree level reached: " + maxLevel);
  
  // Descend first
  for (PTElement child : ai_parseTree_getChildren(parser, productions, e))
    ai_parseTree_makeWeights(parser, productions, child, level+1, maxLevel);
    
  // Then calculate this node's weight
  
  // check for explicit anti-examples
  if (e instanceof HaveCategory && contains(ai_antiWordCategoriesWithElements().get(e/HaveCategory.category), e.text()))
    ret with e.weight = 0.1;
    
  if (e instanceof ChoosePart)
    e.weight = avg(first(e.children).weight, second(e.children).weight);
  else if (e instanceof HaveCategory && empty(e.children))
    e.weight = or(ai_getWordToCategoryWeight(e.text(), e/HaveCategory.category), 1.0);
  else
    e.weight = collectMaxDouble(e.children, 'weight);
    
  ai_Reconstructed r =
    e instanceof ChoosePart ? e/ChoosePart.reconstruction
    : e instanceof HaveCategory ? e/HaveCategory.reconstruction : null;
  if (r != null)
    e.weight *= r.production.weight;
}