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* 🔥 consolidate documentation
* ♻️ overwork std specializations
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* ♻️ fix URLs
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* 📝 document deprecations
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* 🚧 start adding documentation for macros
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* 📝 overwork example handling
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2021-12-29 13:41:01 +01:00

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nlohmann::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 parameters

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.

Examples

??? 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.

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