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# Header only

`json.hpp` is the single required file in `single_include/nlohmann` or released here. You need to add

    #include <nlohmann/json.hpp>

    // for convenience
    using json = nlohmann::json;

to the files you want to process JSON and set the necessary switches to enable C++11 (e.g., `-std=c++11` for GCC and Clang).

You can further use file `include/nlohmann/json_fwd.hpp` for forward-declarations. The installation of `json_fwd.hpp` (as part of CMake's install step), can be achieved by setting `-DJSON_MultipleHeaders=ON`.

Last update: May 1, 2022
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