RapidXLL automatically converts C/C++ libraries into Excel Add-Ins, .NET Libraries, and HTML User Documentation. Place simple tags in your header files and RapidXLL does the rest. Similar tags allow for more sophisticated manipulations (adding help information, controlling function order of function evaluation, building unique object handles, other). The library also supplies classes for Excel ranges (RapidRange), variant values (RapidValue), dates (RapidDate), and long strings (RapidString). These data structures are designed for rapid integration with Excel.