Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
This is an older version of Boost and was released in 2013. The current version is 1.92.0.
boost::local_time::ambiguous_result — simple exception for reporting when STD or DST cannot be determined
struct ambiguous_result { // construct/copy/destruct ambiguous_result(std::string = ""); };