The library provides a large number of tests in the libs/date_time/test libs/date_time/test/gregorian libs/date_time/test/posix_time libs/date_time/test/local_time directories. Building and executing these tests assures that the installation is correct and that the library is functioning correctly. In addition, these tests facilitate the porting to new compilers. Finally, the tests provide examples of many functions not explicitly described in the usage examples.