Loki is the name of a C++ software library written by Andrei Alexandrescu as part of his book Modern C++ Design.
The library makes extensive use of C++ template metaprogramming and implements several commonly used tools: typelist, functor, singleton, smart pointer, object factory, visitor and multimethods.
Originally the library was only compatible with two of the most standard conforming C++ compilers (CodeWarrior and Comeau C/C++): later efforts have made it usable with a wide array of compilers (including older Visual C++ 6.0, Borland C++ Builder 6.0, and GCC). Compiler vendors used Loki as a compatibility benchmark, further increasing the number of compliant compilers.
Maintenance and further development of Loki has been continued through an open-source community led by Peter Kümmel and Richard Sposato as a Sourceforge project.Ongoing contributions by many people have improved the overallrobustness and functionality of the library. Loki is not tied to thebook anymore as it already has a lot of new components (e.g. -StrongPtr, Printf, and Scopeguard). Loki inspired similar tools andfunctionality now also present in the Boost library collection.