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_primitive
is_string
is_structured
list_init_t
max_size
number_float_t
number_integer_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[]
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>

reference nlohmann::basic_json::back | ( |  | ) |

inline

Returns a reference to the last element in the container. For a JSON container `c`, the expression `c.back()` is equivalent to `{ auto tmp = c.end(); --tmp; return *tmp; }`.

Returns
  In case of a structured type (array or object), a reference to the last element is returned. In cast of number, string, or boolean values, a reference to the value is returned.

Complexity
  Constant.

Note
  Calling `back` on an empty container is undefined.

Exceptions

  std::out_of_range | when called on null value.

Example
  The following code shows an example for back.
  #include <json.hpp>
  using namespace nlohmann;
  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_object_empty(json::value_t::object);
  json j_array = {1, 2, 4, 8, 16};
  json j_array_empty(json::value_t::array);
  json j_string = "Hello, world";
  // call back()
  //std::cout << j_null.back() << '\n'; // would throw
  std::cout << j_boolean.back() << '\n';
  std::cout << j_number_integer.back() << '\n';
  std::cout << j_number_float.back() << '\n';
  std::cout << j_object.back() << '\n';
  //std::cout << j_object_empty.back() << '\n'; // would throw
  std::cout << j_array.back() << '\n';
  //std::cout << j_array_empty.back() << '\n'; // would throw
  std::cout << j_string.back() << '\n';
  }
  nlohmann::basic_json::back
  reference back()
  access the last element
  Definition: json.hpp:2427
  nlohmann::basic_json
  a class to store JSON values
  Definition: json.hpp:121
  nlohmann::basic_json::value_t::object
  object (unordered set of name/value pairs)
  nlohmann
  namespace for Niels Lohmann
  Definition: json.hpp:56
  nlohmann::basic_json::value_t::array
  array (ordered collection of values)
  Output:

      true
      17
      23.42
      2
      16
      "Hello, world"

  The example code above can be translated with

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

  .