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
basic_json
basic_json
basic_json
basic_json
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+=
operator+=
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
| ## § get_ref() [1/2] 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> template<typename ReferenceType , typename std::enable_if< std::is_reference< ReferenceType >::value, int >::type = 0>
ReferenceType nlohmann::basic_json::get_ref | ( |  | ) |
| inline
  Implict reference access to the internally stored JSON value. No copies are made. Warning Writing data to the referee of the result yields an undefined state. Template Parameters
  ReferenceType | reference type; must be a reference to array_t, object_t, string_t, boolean_t, number_integer_t, or number_float_t. Enforced by static assertion.
  Returns reference to the internally stored JSON value if the requested reference type ReferenceType fits to the JSON value; throws std::domain_error otherwise Exceptions
  std::domain_error | in case passed type ReferenceType is incompatible with the stored JSON value
  Complexity Constant. Example The example shows several calls to `get_ref()`. 1 #include <json.hpp> 2 3 using json = nlohmann::json; 4 5 int main() 6 { 7 // create a JSON number 8 json value = 17; 9 10 // explicitly getting references 11 auto r1 = value.get_ref<const json::number_integer_t&>(); 12 auto r2 = value.get_ref<json::number_integer_t&>(); 13 14 // print the values 15 std::cout << r1 << ' ' << r2 << '\n'; 16 17 // incompatible type throws exception 18 try 19 { 20 auto r3 = value.get_ref<json::number_float_t&>(); 21 } 22 catch (std::domain_error& ex) 23 { 24 std::cout << ex.what() << '\n'; 25 } 26 } nlohmann::json basic_json<> json default JSON class Definition: json.hpp:12151 nlohmann::basic_json::number_integer_t NumberIntegerType number_integer_t a type for a number (integer) Definition: json.hpp:580 nlohmann::basic_json::value ValueType value(const typename object_t::key_type &key, ValueType default_value) const access specified object element with default value Definition: json.hpp:3675 nlohmann::basic_json::number_float_t NumberFloatType number_float_t a type for a number (floating-point) Definition: json.hpp:719 Output (play with this example online):
      17 17
      incompatible ReferenceType for get_ref, actual type is number
  The example code above can be translated with
      g++ -std=c++11 -Isrc doc/examples/get_ref.cpp -o get_ref
Since version 1.1.0 Definition at line 3046 of file json.hpp.