JSON for Modern C++ 2.1.1
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◆ type_name()

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>
std::string nlohmann::basic_json< ObjectType, ArrayType, StringType, BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType, AllocatorType, JSONSerializer >::type_name ( ) const
inline

Returns the type name as string to be used in error messages - usually to indicate that a function was called on a wrong JSON type.

Returns
basically a string representation of a the m_type member
Complexity\n Constant.
Example\n The following code exemplifies type_name() for all JSON
types.
1#include <json.hpp>
2
3using json = nlohmann::json;
4
5int main()
6{
7 // create JSON values
9 json j_boolean = true;
11 json j_number_float = 23.42;
12 json j_object = {{"one", 1}, {"two", 2}};
13 json j_array = {1, 2, 4, 8, 16};
14 json j_string = "Hello, world";
15
16 // call type_name()
17 std::cout << j_null.type_name() << '\n';
18 std::cout << j_boolean.type_name() << '\n';
19 std::cout << j_number_integer.type_name() << '\n';
20 std::cout << j_number_float.type_name() << '\n';
21 std::cout << j_object.type_name() << '\n';
22 std::cout << j_array.type_name() << '\n';
23 std::cout << j_string.type_name() << '\n';
24}
static basic_json array(std::initializer_list< basic_json > init=std::initializer_list< basic_json >())
explicitly create an array from an initializer list
Definition json.hpp:2165
std::string type_name() const
return the type as string
Definition json.hpp:8065
a class to store JSON values
Definition json.hpp:1040
basic_json<> json
default JSON class
Definition json.hpp:12369

Output (play with this example online):
null
boolean
number
number
object
array
string

The example code above can be translated with
g++ -std=c++11 -Isrc doc/examples/type_name.cpp -o type_name 
Since
version 1.0.0, public since 2.1.0

Definition at line 8065 of file json.hpp.