whole_func_string: function selfLinking(link, id) {
    return getNodeID(link.source, id) == getNodeID(link.target, id);
  }
func_code_string: function selfLinking(link, id) {
    return getNodeID(link.source, id) == getNodeID(link.target, id);
  }
func_documentation_string: check if link is self linking, ie links a node to the same node