UPDATE 2020: Today I would probably go with Lua + Sol2/3 except if I really want to avoid Lua as a language. Chaiscript becomes a good candidate in this case though it is not optimal performance-wise compared to Lua+Sol2/3 (though it was greatly improved through years so it is still good enough in many cases).
Falcon have been dead for some years, RIP.
The following ones are more C++ integration oriented than language bindings :
- ChaiScript – trying at the moment in a little project, interesting, this one is MADE with C++ in mind and works by just including a header! Not sure if it’s good for a big project yet but will see, try it to have some taste!
- (not maintained anymore) Falcon – trying on a big project, excellent; it’s not a “one include embed” as ChaiScript but it’s because it’s really flexible, and totally thought to be used in C++ (only C++ code in libs) – I’ve decided to stick with it for my biggest project that require a lot of scripting flexibility (comparable to ruby/python )
- AngelScript – didn’t try yet
- GameMonkey – didn’t try yet
- Io – didn’t try yet
For you, if you really want to write your scripting module in C++ and easily expose it to the scripting language, I would recommand going with Falcon. It’s totally MADE in C++, all the modules/libraries are written that way.