JSON for Modern C++ 2.0.10

allocator_type
array
array_t
at
at
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
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basic_json
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basic_json
basic_json
begin
begin
boolean_t
cbegin
cend
clear
const_iterator
const_pointer
const_reference
const_reverse_iterator
count
crbegin
crend
diff
difference_type
dump
emplace
emplace_back
empty
end
end
erase
erase
erase
erase
find
find
flatten
from_cbor
from_msgpack
front
front
get
get
get
get_allocator
get_ptr
get_ptr
get_ref
get_ref
insert
insert
insert
insert
insert
is_array
is_boolean
is_discarded
is_null
is_number
is_number_float
is_number_integer
is_number_unsigned
is_object
is_primitive
is_string
is_structured
iterator
iterator_wrapper
iterator_wrapper
max_size
number_float_t
number_integer_t
number_unsigned_t
object
object_t
operator value_t
operator ValueType
operator!=
operator!=
operator!=
operator+=
operator+=
operator+=
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operator<
operator<
operator<<
operator<<
operator<=
operator=
operator==
operator==
operator==
operator>
operator>=
operator>>
operator>>
operator[]
operator[]
operator[]
operator[]
operator[]
operator[]
operator[]
operator[]
operator[]
operator[]
parse
parse
parse
parse
parse
parse
parse_event_t
parser_callback_t
patch
pointer
push_back
push_back
push_back
push_back
rbegin
rbegin
reference
rend
rend
reverse_iterator
size
size_type
string_t
swap
swap
swap
swap
to_cbor
to_msgpack
type
unflatten
value
value
value
value
value_t
value_type
~basic_json
| ## § at() [2/6] 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>
const_reference nlohmann::basic_json::at | ( | size_type | idx | ) | const
| inline
  Returns a const reference to the element at specified location idx, with bounds checking. Parameters
  [in] | idx | index of the element to access
  Returns const 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 using `at()`. 1 #include <json.hpp> 2 3 using json = nlohmann::json; 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 // try to read beyond the array limit 14 try 15 { 16 std::cout << array.at(5) << '\n'; 17 } 18 catch (std::out_of_range) 19 { 20 std::cout << "out of range" << '\n'; 21 } 22 } nlohmann::json basic_json<> json default JSON class Definition: json.hpp:12151 Output (play with this example online):
      "third"
      out of range
  The example code above can be translated with
      g++ -std=c++11 -Isrc doc/examples/at__size_type_const.cpp -o at__size_type_const
Since version 1.0.0 Definition at line 3182 of file json.hpp.