flex++ and bison++ were created from flex and bison by A. Coetmeur in the 1990s. These two programs provided seamless integration with C++, allowing developers to code actions in C++ and call private member functions of a parent class. This makes it straightforward to embed a parser and scanner by private inheritance, creating a clean “compiler” class which need expose only the results of the parsing. For these and other reasons, flex++ and bison++ impressed me as being well-engineered when I first discovered them, and I still prefer their approach to C++ integration.

Releases of flex++ and bison++ ended in 1993 and they fell out of date as C++, gcc, flex,and bison all evolved. New releases of gcc would often reject the generated parser and lexer code because it no longer conformed to the evolving C++ standard. To keep two legacy programs that used flex++ and bison++ afloat, I was making hasty, on-the-fly patches whenever a new version of gcc arrived.

No pre-built flex++/bison++ packages are available for openSUSE (as of this post). So recently I loaded the 1993 releases into Google Project Hosting and updated them more carefully to build cleanly under gcc 4.5 and generate code that compiles and links cleanly under g++ 4.5. I also added a configure file to flex++, which was so old it didn’t have one.

If you’ve arrived here by following the Contact Page link from the Google Project page, leave a comment and I’ll get back to you.