mirror of
https://github.com/nlohmann/json.git
synced 2026-07-09 12:05:10 +00:00
nlohmann
51 lines
974 B
Markdown
51 lines
974 B
Markdown
# nlohmann::basic_json::boolean_t
|
|
|
|
```
|
|
using boolean_t = BooleanType;
|
|
```
|
|
|
|
The type used to store JSON booleans.
|
|
|
|
[RFC 8259](https://tools.ietf.org/html/rfc8259) implicitly describes a boolean as a type which differentiates the two literals `true` and `false`.
|
|
|
|
To store boolean values in C++, a type is defined by the template parameter `BooleanType` which chooses the type to use.
|
|
|
|
## Notes
|
|
|
|
#### Default type
|
|
|
|
With the default values for `BooleanType` (`bool`), the default value for `boolean_t` is `bool`.
|
|
|
|
#### Storage
|
|
|
|
Boolean values are stored directly inside a `basic_json` type.
|
|
|
|
## Examples
|
|
|
|
Example
|
|
|
|
The following code shows that `boolean_t` is by default, a typedef to `bool`.
|
|
|
|
```
|
|
#include <iostream>
|
|
#include <iomanip>
|
|
#include <nlohmann/json.hpp>
|
|
|
|
using json = nlohmann::json;
|
|
|
|
int main()
|
|
{
|
|
std::cout << std::boolalpha << std::is_same<bool, json::boolean_t>::value << std::endl;
|
|
}
|
|
```
|
|
|
|
Output:
|
|
|
|
```
|
|
true
|
|
```
|
|
|
|
## Version history
|
|
|
|
- Added in version 1.0.0.
|