# <small>nlohmann::basic_json_view::</small>is_null

```cpp
bool is_null() const noexcept;
```

This function returns `#!cpp true` if and only if the value is `#!json null`.

## Return value

`#!cpp true` if the type is `#!json null`, `#!cpp false` otherwise.

## Exception safety

No-throw guarantee: this function never throws exceptions.

## Complexity

Constant.

## Examples

??? example

    The example below classifies several parsed documents by the type of their root value, without materializing any
    of them into a `BasicJsonType` value.

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

    Output:

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

## See also

- [`type`](type.md) - return the type of the value
- [`BasicJsonType::is_null`](../basic_json/is_null.md) - the corresponding function of `basic_json`

## Version history

- Added in version 3.13.0.