Each library present in this site has the link to an associated page explaining its motivations and use, which in turn has a link to the GitHub source code. The libraries’ internals aren’t described, as the codes are thoroughly commented and that should be enough. If not, don’t hesitate to contact me so that I can improve them.
Product iterator is a C++ library designed to perform the Cartesian product of containers in a clean and efficient way. Inspired by Boost.Iterator, it builds tuples of each combination of elements in the containers in a lazy way, so that they are built as required.