Exporting and Installing
There are three good ways and one bad way to allow others use your library:
If you are the library author, don't make a
Find<mypackage>.cmakescript! These were designed for libraries whose authors did not support CMake. Use a
Config<mypackage>.cmakeinstead as listed below.
A package can include your project in a subdirectory, and then use
add_directoryon the subdirectory. This useful for header-only and quick-to-compile libraries. Note that the install commands may interfere with the parent project, so you can add
add_subdirectorycommand; the targets you explicitly use will still be built.
In order to support this as a library author, make sure you use
PROJECT_SOURCE_DIR(and likewise for other variables, like binary dirs). You can check
CMAKE_PROJECT_NAME STREQUAL PROJECT_NAMEto only add options or defaults that make sense if this is a project.
Also, since namespaces are a good idea, and the usage of your library should be consistent with the other methods below, you should add
add_library(MyLib::MyLib ALIAS MyLib)
to standardise the usage across all methods. This ALIAS target will not be exported below.
The third way is
*Config.cmakescripts; that will be the topic of the next chapter in this session.