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 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 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 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[] parse parse parse parse parse parse 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_name unflatten value value value value value_t value_type ~basic_json

operator value_t() 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> constexpr nlohmann::basic_json< ObjectType, ArrayType, StringType, BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType, AllocatorType, JSONSerializer >::operator value_t ( ) const inlinenoexcept Implicitly return the type of the JSON value as a value from the value_t enumeration. Returns the type of the JSON value Complexity Constant. Exception safety No-throw guarantee: this member function never throws exceptions. Example The following code exemplifies the value_t operator for all JSON types. #include <json.hpp> using json = nlohmann::json; int main() { // create JSON values json j_null; json j_boolean = true; json j_number_integer = 17; json j_number_float = 23.42; json j_object = {{"one", 1}, {"two", 2}}; json j_array = {1, 2, 4, 8, 16}; json j_string = "Hello, world"; // call operator value_t() json::value_t t_null = j_null; json::value_t t_boolean = j_boolean; json::value_t t_number_integer = j_number_integer; json::value_t t_number_float = j_number_float; json::value_t t_object = j_object; json::value_t t_array = j_array; json::value_t t_string = j_string; // print types std::cout << std::boolalpha; std::cout << (t_null == json::value_t::null) << '\n'; std::cout << (t_boolean == json::value_t::boolean) << '\n'; std::cout << (t_number_integer == json::value_t::number_integer) << '\n'; std::cout << (t_number_float == json::value_t::number_float) << '\n'; std::cout << (t_object == json::value_t::object) << '\n'; std::cout << (t_array == json::value_t::array) << '\n'; std::cout << (t_string == json::value_t::string) << '\n'; } Output (play with this example online): true true true true true true true The example code above can be translated with g++ -std=c++11 -Isrc doc/examples/operator__value_t.cpp -o operator__value_t Since version 1.0.0 Definition at line 3020 of file json.hpp.