basic_json::get_ref

template<typename ReferenceType>
ReferenceType get_ref();

template<typename ReferenceType>
const ReferenceType get_ref() const;

Implicit reference access to the internally stored JSON value. No copies are made.

Template arguments

ReferenceType : reference type; must be a reference to array_t, object_t, string_t, boolean_t, number_integer_t, or number_unsigned_t, number_float_t, or binary_t. Enforced by static assertion.

Return value

reference to the internally stored JSON value if the requested reference type fits to the JSON value; throws type_error.303 otherwise

Exception safety

Strong exception safety: if an exception occurs, the original value stays intact.

Exceptions

Throws type_error.303 if the requested reference type does not match the stored JSON value type; example: "incompatible ReferenceType for get_ref, actual type is binary".

Complexity

Constant.

Notes

!!! warning

Writing data to the referee of the result yields an undefined state.

Example

??? example

The example shows several calls to `get_ref()`.

```cpp
--8<-- "examples/get_ref.cpp"
```

Output:

```json
--8<-- "examples/get_ref.output"
```

Version history

  • Added in version 1.1.0.
  • Extended to binary types in version 3.8.0.