JSON for Modern C++  2.0.3

§ swap() [2/4]

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>
void nlohmann::basic_json::swap ( array_t other)
inline

Exchanges the contents of a JSON array with those of other. Does not invoke any move, copy, or swap operations on individual elements. All iterators and references remain valid. The past-the-end iterator is invalidated.

Parameters
[in,out]otherarray to exchange the contents with
Exceptions
std::domain_errorwhen JSON value is not an array; example: "cannot use swap() with string"
Complexity
Constant.
Example
The example below shows how arrays can be swapped with swap().
1 #include <json.hpp>
2 
3 using json = nlohmann::json;
4 
5 int main()
6 {
7  // create a JSON value
8  json value = {{"array", {1, 2, 3, 4}}};
9 
10  // create an array_t
11  json::array_t array = {"Snap", "Crackle", "Pop"};
12 
13  // swap the array stored in the JSON value
14  value["array"].swap(array);
15 
16  // output the values
17  std::cout << "value = " << value << '\n';
18  std::cout << "array = " << array << '\n';
19 }
basic_json<> json
default JSON class
Definition: json.hpp:10122
ArrayType< basic_json, AllocatorType< basic_json >> array_t
a type for an array
Definition: json.hpp:437
Output (play with this example online):
value = {"array":["Snap","Crackle","Pop"]}
array = [1,2,3,4]
The example code above can be translated with
g++ -std=c++11 -Isrc doc/examples/swap__array_t.cpp -o swap__array_t 
Since
version 1.0.0

Definition at line 5308 of file json.hpp.