Github issue:
https://github.com/nlohmann/json/issues/2073
nlohmann::json documents 2 way of depending on it using CMake
1) Copy-paste the project/source into your own project.
2) Install nlohman::json and then use find_package.
(1) pollutes your git repository, (2) requires everyone to install the
dependencies themselves.
Since 2018, CMake provide some kind of 'package manager' features using
[FetchContent](https://cmake.org/cmake/help/v3.17/module/FetchContent.html)
It gives the following:
~~~cmake
include(FetchContent)
FetchContent_Declare(json
GIT_REPOSITORY https://github.com/nlohmann/json
GIT_TAG v3.7.3)
FetchContent_GetProperties(json)
if(NOT json_POPULATED)
FetchContent_Populate(json)
add_subdirectory( ${json_SOURCE_DIR} ${json_BINARY_DIR} EXCLUDE_FROM_ALL)
endif()
~~~
Then declares the dependency in the target using it:
~~~cmake
target_link_library(my_project PRIVATE nlohmann_json::nlohmann_json
~~~
This patch updates the documentation and provides tests.
