allocator_type array array_t at at at at at at back back basic_json basic_json basic_json basic_json basic_json basic_json basic_json basic_json begin begin boolean_t cbegin cend clear const_iterator const_pointer const_reference const_reverse_iterator count crbegin crend detail::external_constructor diff difference_type dump emplace emplace_back empty end end erase erase erase erase exception find find flatten from_cbor from_msgpack front front get get get get get get_allocator get_ptr get_ptr get_ref get_ref insert insert insert insert insert insert invalid_iterator is_array is_boolean is_discarded is_null is_number is_number_float is_number_integer is_number_unsigned is_object is_primitive is_string is_structured iterator iterator_wrapper iterator_wrapper json_serializer max_size meta number_float_t number_integer_t number_unsigned_t object object_t operator value_t operator ValueType operator!= operator!= operator!= operator+= operator+= operator+= operator+= operator< operator< operator< operator<< operator<< operator<= operator<= operator<= operator= operator== operator== operator== operator> operator> operator> operator>= operator>= operator>= operator>> operator>> operator[] operator[] operator[] operator[] operator[] operator[] operator[] operator[] operator[] operator[] other_error out_of_range parse parse parse parse parse parse parse_error parse_event_t parser_callback_t patch pointer push_back push_back push_back push_back rbegin rbegin reference rend rend reverse_iterator size size_type string_t swap swap swap swap to_cbor to_msgpack type type_error type_name unflatten value value value value value_t value_type ~basic_json

from_msgpack() template<template< typename U, typename V, typename... Args > class ObjectType = std::map, template< typename U, typename... Args > class ArrayType = std::vector, class StringType = std::string, class BooleanType = bool, class NumberIntegerType = std::int64_t, class NumberUnsignedType = std::uint64_t, class NumberFloatType = double, template< typename U > class AllocatorType = std::allocator, template< typename T, typename SFINAE=void > class JSONSerializer = adl_serializer> static basic_json nlohmann::basic_json::from_msgpack ( const std::vector< uint8_t > &  v, const size_t  start_index = 0  ) inlinestatic Deserializes a given byte vector v to a JSON value using the MessagePack serialization format. The library maps MessagePack types to JSON value types as follows: MessagePack type JSON value type first byte positive fixint number_unsigned 0x00..0x7f fixmap object 0x80..0x8f fixarray array 0x90..0x9f fixstr string 0xa0..0xbf nil null 0xc0 false false 0xc2 true true 0xc3 float 32 number_float 0xca float 64 number_float 0xcb uint 8 number_unsigned 0xcc uint 16 number_unsigned 0xcd uint 32 number_unsigned 0xce uint 64 number_unsigned 0xcf int 8 number_integer 0xd0 int 16 number_integer 0xd1 int 32 number_integer 0xd2 int 64 number_integer 0xd3 str 8 string 0xd9 str 16 string 0xda str 32 string 0xdb array 16 array 0xdc array 32 array 0xdd map 16 object 0xde map 32 object 0xdf negative fixint number_integer 0xe0-0xff Warning The mapping is incomplete in the sense that not all MessagePack types can be converted to a JSON value. The following MessagePack types are not supported and will yield parse errors: bin 8 - bin 32 (0xc4..0xc6) ext 8 - ext 32 (0xc7..0xc9) fixext 1 - fixext 16 (0xd4..0xd8) Note Any MessagePack output created to_msgpack can be successfully parsed by from_msgpack. Parameters [in] v a byte vector in MessagePack format [in] start_index the index to start reading from v (0 by default) Returns deserialized JSON value Exceptions parse_error.110 if the given vector ends prematurely parse_error.112 if unsupported features from MessagePack were used in the given vector v or if the input is not valid MessagePack parse_error.113 if a string was expected as map key, but not found Complexity Linear in the size of the byte vector v. Example The example shows the deserialization of a byte vector in MessagePack format to a JSON value. #include "json.hpp" #include <iomanip> // for std::setw using json = nlohmann::json; int main() { // create byte vector std::vector<uint8_t> v = {0x82, 0xa7, 0x63, 0x6f, 0x6d, 0x70, 0x61, 0x63, 0x74, 0xc3, 0xa6, 0x73, 0x63, 0x68, 0x65, 0x6d, 0x61, 0x00 }; // deserialize it with MessagePack json j = json::from_msgpack(v); // print the deserialized JSON value std::cout << std::setw(2) << j << std::endl; } Output (play with this example online): { "compact": true, "schema": 0 } The example code above can be translated with g++ -std=c++11 -Isrc doc/examples/from_msgpack.cpp -o from_msgpack See also http://msgpack.org to_msgpack(const basic_json&) for the analogous serialization from_cbor(const std::vector<uint8_t>&, const size_t) for the related CBOR format Since version 2.0.9, parameter start_index since 2.1.1 Definition at line 9178 of file json.hpp.