# nlohmann::json_pointer::back ```cpp const string_t& back() const; ``` Return the last reference token. ## Return value Last reference token. ## Exceptions Throws [out_of_range.405](../../home/exceptions.md#jsonexceptionout_of_range405) if the JSON pointer has no parent. ## Complexity Constant. ## Examples ??? example The example shows the usage of `back`. ```cpp --8<-- "examples/json_pointer__back.cpp" ``` Output: ```json --8<-- "examples/json_pointer__back.output" ``` ## Version history - Added in version 3.6.0. - Changed return type to `string_t` in version 3.11.0.