# basic_json::to_msgpack ```cpp // (1) static std::vector to_msgpack(const basic_json& j); // (2) static void to_msgpack(const basic_json& j, detail::output_adapter o); static void to_msgpack(const basic_json& j, detail::output_adapter o); ``` Serializes a given JSON value `j` to a byte vector using the MessagePack serialization format. MessagePack is a binary serialization format which aims to be more compact than JSON itself, yet more efficient to parse. 1. Returns a byte vector containing the MessagePack serialization. 2. Writes the MessagePack serialization to an output adapter. ## Parameters `j` (in) : JSON value to serialize `o` (in) : output adapter to write serialization to ## Return value 1. MessagePack serialization as byte vector 2. / ## Exception safety Strong guarantee: if an exception is thrown, there are no changes in the JSON value. ## Complexity Linear in the size of the JSON value `j`. ## Example ??? example The example shows the serialization of a JSON value to a byte vector in MessagePack format. ```cpp --8<-- "examples/to_msgpack.cpp" ``` Output: ```json --8<-- "examples/to_msgpack.output" ``` ## Version history - Added in version 2.0.9.