__basic_json
allocator_type
array
array_t
at
at
at
at
back
back
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
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_pointer
const_reference
count
crbegin
crend
difference_type
dump
empty
end
end
erase
erase
erase
erase
find
find
front
front
get
get
get_allocator
get_ptr
is_array
is_boolean
is_discarded
is_null
is_number
is_number_float
is_number_integer
is_object
is_string
list_init_t
max_size
number_float_t
number_integer_t
object
object_t
operator T
operator value_t
operator!=
operator+=
operator+=
operator+=
operator<
operator<
operator<<
operator<<
operator<=
operator=
operator==
operator>
operator>=
operator>>
operator>>
operator[]
operator[]
operator[]
operator[]
operator[]
operator[]
parse
parse
parse_event_t
parser_callback_t
pointer
push_back
push_back
push_back
rbegin
rbegin
reference
rend
rend
size
size_type
string_t
swap
swap
swap
swap
type
value_t
value_type
~basic_json

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 = int64_t, class NumberFloatType = double, template< typename U > class AllocatorType = std::allocator>
template<typename T >

nlohmann::basic_json::operator T | ( |  | ) | const

inline

Implict type conversion between the JSON value and a compatible value. The call is realized by calling get() const.

Template Parameters

  T | type compatible to the JSON value, for instance `int` for JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for JSON arrays

Returns
  copy of the JSON value, converted to type T

Exceptions

  std::domain_error | in case passed type T is incompatible to JSON, thrown by get() const

Complexity
  Linear in the size of the JSON value.

Example
  The example below shows serveral conversions from JSON values to other types. There a few things to note: (1) Floating-point numbers can be converted to integers, (2) A JSON array can be converted to a standard `std::vector<int>`, (3) A JSON object can be converted to C++ assiciative containers such as `std::unordered_map<std::string, json>`.
  #include <json.hpp>
  #include <unordered_map>
  using namespace nlohmann;
  int main()
  {
  // create a JSON value with different types
  json json_types =
  {
  {"boolean", true},
  {
  "number", {
  {"integer", 42},
  {"floating-point", 17.23}
  }
  },
  {"string", "Hello, world!"},
  {"array", {1, 2, 3, 4, 5}},
  {"null", nullptr}
  };
  // use implicit conversions
  bool v1 = json_types["boolean"];
  int v2 = json_types["number"]["integer"];
  short v3 = json_types["number"]["integer"];
  float v4 = json_types["number"]["floating-point"];
  int v5 = json_types["number"]["floating-point"];
  std::string v6 = json_types["string"];
  std::vector<short> v7 = json_types["array"];
  std::unordered_map<std::string, json> v8 = json_types;
  // print the conversion results
  std::cout << v1 << '\n';
  std::cout << v2 << ' ' << v3 << '\n';
  std::cout << v4 << ' ' << v5 << '\n';
  std::cout << v6 << '\n';
  for (auto i : v7)
  {
  std::cout << i << ' ';
  }
  std::cout << "\n\n";
  for (auto i : v8)
  {
  std::cout << i.first << ": " << i.second << '\n';
  }
  }
  nlohmann::basic_json
  a class to store JSON values
  Definition: json.hpp:121
  nlohmann
  namespace for Niels Lohmann
  Definition: json.hpp:56
  Output:

      1
      42 42
      17.23 17
      Hello, world!
      1 2 3 4 5

      string: "Hello, world!"
      number: {"floating-point":17.23,"integer":42}
      null: null
      boolean: true
      array: [1,2,3,4,5]

  The example code above can be translated with

      g++ -std=c++11 -Isrc doc/examples/operator__T.cpp -o operator__T

  .