json/api/macros/json_has_three_way_comparison.md

JSON_HAS_THREE_WAY_COMPARISON

#define JSON_HAS_THREE_WAY_COMPARISON /* value */

This macro indicates whether the compiler and standard library support 3-way comparison. Possible values are 1 when supported or 0 when unsupported.

Default definition

The default value is detected based on the preprocessor macros #!cpp __cpp_impl_three_way_comparison and #!cpp __cpp_lib_three_way_comparison.

When the macro is not defined, the library will define it to its default value.

Examples

??? example

The code below forces the library to use 3-way comparison:

```cpp
#define JSON_HAS_THREE_WAY_COMPARISON 1
#include <nlohmann/json.hpp>

...
```

Version history

• Added in version 3.11.0.