cxxfn (pronounced "cexx-fun") creates C++ std::function objects directly from Rust for the purposes of interaction with C++ dynamic libraries.

Are you getting hot and sweaty with a C++ dylib? Does the library expect you to pass in std::function objects? Are you under a religious obligation to not use any C++ glue code? In that case, cxxfn may be just what you're looking for.

Interacting with C++ is fraught with danger and unsafety, and std::function especially is quite dangerous. This library tries to make the API mostly safe for all users involved, but there are very little guarantees that really can be made with FFI. It is therefore quite likely that you'll catch the C++ std unsafety as well: sometimes that is the price of having a little cxxfn.

If you do not need this, do not look at this.

Few years ago, I gave a talk about doing FFI crimes with a C++ dynamic library, including creating std::function objects on the wrong side of the boundary. After the talk, a listener came to give me their business card upon which they had written the above abbreviation. They explained that it stands for the following phrase:

Your kink is not my kink, but your kink is okay.

If you're thinking of using this library, then your kink is probably the same as my kink, and it is very much okay!