code: function forwardSearch() {
        cameFrom = open1Set.pop();
        if (cameFrom.closed) {
          return;
        }
  
        cameFrom.closed = true;
  
        if (cameFrom.f1 < lMin && (cameFrom.g1 + f2 - heuristic(from, cameFrom.node)) < lMin) {
          graph.forEachLinkedNode(cameFrom.node.id, forwardVisitor);
        }
  
        if (open1Set.length > 0) {
          // this will be used in reverse search
          f1 = open1Set.peek().f1;
        } 
      }
docs: the public API is over