code: func (it *Resolver) resolve(ctx context.Context) error {
  	values, err := graph.RefsOf(ctx, it.qs, it.order)
  	if err != nil {
  		return err
  	}
  	for index, value := range values {
  		node := it.order[index]
  		it.values[node] = value
  		it.nodes[value.Key()] = node
  	}
  	it.cached = true
  	return nil
  }
docs: // Resolve nodes to values