json/api/basic_json/operator_value_t.md

nlohmann::basic_json::operator value_t

constexpr operator value_t() const noexcept;

Return the type of the JSON value as a value from the value_t enumeration.

Return value

the type of the JSON value

Value type	return value
#!json null	value_t::null
boolean	value_t::boolean
string	value_t::string
number (integer)	value_t::number_integer
number (unsigned integer)	value_t::number_unsigned
number (floating-point)	value_t::number_float
object	value_t::object
array	value_t::array
binary	value_t::binary
discarded	value_t::discarded

Exception safety

No-throw guarantee: this member function never throws exceptions.

Complexity

Constant.

Examples

??? example

The following code exemplifies `operator value_t()` for all JSON types.

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

Output:

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

Version history

• Added in version 1.0.0.
• Added unsigned integer type in version 2.0.0.
• Added binary type in version 3.8.0.