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c++boostcmakeboost-hana

Using boost::hana and CMake without full boost install (external project?)

I recently downloaded the newest boost library to get access to boost::hana and read on their documentation page that they suggest using the "FindHana.cmake module to setup Hana as an external project for use."

I couldn't figure this out so I just set the compile flags to include my hana.hpp to the header path, but I'd love to know how to accomplish this the way suggested in the documentation.

Solution

  • In upcoming versions of Boost, Hana provides a file called HanaConfig.cmake, which is installed in <install-prefix>/lib/cmake/hana/HanaConfig.cmake automatically when you type make install. Then, provided your <install-prefix> is part of the CMAKE_PREFIX_PATH (which will be the case if you install it to a default, system-wide location), you just need to:

    find_package(Hana)
target_link_libraries(some-target hana)

    This will add the right include directories to some-target. This is the right way to depend on other CMake projects, and I changed Hana's way of doing it recently (on develop only right now) in light of this.