luawrapper | Easy-to-use lua wrapper for C

Is there some easier way to generate a binder function from the type signature of the lambda supplied?

The short answer is “No”.

Generally, you could use standard library equivalents, std::function, std::bind, std::placeholders. The implementation code is even more complex. But they're in the standard library, i.e. you don’t have to support that code, and you’ll get documentation.

For this particular case, however, they won’t work. Because the function doesn’t just make a callable thing like std::function, instead it marshals the arguments + return value to LUA.

Other methods exist, but they aren’t necessarily simpler. Sometimes C #defines leads to simpler code. In other cases, external scripts or tools running in a pre-build step generate the boilerplate code from something else (special comments/other markup in your source, or external LUA code, or external protocol/interface definitions).

Generally, to write code like this, reflection support in the programming language helps. Unfortunately, C++ has no reflection. Hence that write-only template code.