JSON for Modern C++ 1.0.0

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~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::at | ( | size_type | idx | ) |
| inline
  Returns a reference to the element at specified location idx, with bounds checking. Parameters
  [in] | idx | index of the element to access
  Returns reference to the element at index idx Exceptions
  std::domain_error | if the JSON value is not an array; example: `"cannot use at() with string"`
  std::out_of_range | if the index idx is out of range of the array; that is, `idx >= size()`; example: `"array index 7 is out of range"`
  Complexity Constant. Example The example below shows how array elements can be read and written using at. 1 #include <json.hpp> 2 3 using namespace nlohmann; 4 5 int main() 6 { 7 // create JSON array 8 json array = {"first", "2nd", "third", "fourth"}; 9 10 // output element at index 2 (third element) 11 std::cout << array.at(2) << '\n'; 12 13 // change element at index 1 (second element) to "second" 14 array.at(1) = "second"; 15 16 // output changed array 17 std::cout << array << '\n'; 18 19 // try to write beyond the array limit 20 try 21 { 22 array.at(5) = "sixth"; 23 } 24 catch (std::out_of_range& e) 25 { 26 std::cout << "out of range: " << e.what() << '\n'; 27 } 28 } nlohmann::basic_json::array 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:1479 nlohmann::basic_json a class to store JSON values Definition: json.hpp:191 nlohmann::basic_json::at reference at(size_type idx) access specified array element with bounds checking Definition: json.hpp:2729 nlohmann namespace for Niels Lohmann Definition: json.hpp:88 Output (play with this example online):
      "third"
      ["first","second","third","fourth"]
      out of range: array index 5 is out of range
  The example code above can be translated with
      g++ -std=c++11 -Isrc doc/examples/at__size_type.cpp -o at__size_type
Since version 1.0.0 Definition at line 2729 of file json.hpp.