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# JSON_HAS_CPP_11, JSON_HAS_CPP_14, JSON_HAS_CPP_17, JSON_HAS_CPP_20

    #define JSON_HAS_CPP_11
    #define JSON_HAS_CPP_14
    #define JSON_HAS_CPP_17
    #define JSON_HAS_CPP_20

The library targets C++11, but also supports some features introduced in later C++ versions (e.g., `std::string_view` support for C++17). For these new features, the library implements some preprocessor checks to determine the C++ standard. By defining any of these symbols, the internal check is overridden and the provided C++ version is unconditionally assumed. This can be helpful for compilers that only implement parts of the standard and would be detected incorrectly.

## Default definition

The default value is detected based on preprocessor macros such as `__cplusplus`, `_HAS_CXX17`, or `_MSVC_LANG`.

## Notes

- `JSON_HAS_CPP_11` is always defined.
- All macros are undefined outside the library.

## Examples

Example

The code below forces the library to use the C++14 standard:

    #define JSON_HAS_CPP_14 1
    #include <nlohmann/json.hpp>

    ...

## Version history

- Added in version 3.10.5.

Last update: May 17, 2022
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