namespace for Niels Lohmann https://github.com/nlohmann default specialization specialization that maintains the insertion order of object keys deserialize from stream The left operand The right operand deserialize from stream The left operand The right operand serialize to stream The left operand The right operand serialize to stream The left operand The right operand basic_json exchanges the values the type of an element reference the type of an element reference exchanges the values the type of an element reference the type of an element reference deserialize from stream The left operand The right operand serialize to stream Reference to the current output stream An output stream The object to output deserialize from stream The left operand The right operand basic_json serialize to stream Reference to the current output stream An output stream The object to output