Simple CMakeLists.txt which creates conan recipes for the existing system libraries
Clone the project and then run following command
cmake -DLIBRARIES=re2 .
which will try to detect the requested library. Now this library has to be imported into conan with following command
conan create ~/ConanExternal/re2/ --channel systemlib --user admin
and after the file default has been appended to the conan profile
the library should be ready to be consumed.