That seems right, in the paper he is pretty open to the idea of extending the language if the solution is general enough: "In the future, we would like to impl

That seems right, in the paper he is pretty open to the idea of extending the language if the solution is general enough: "In the future, we would like to implement an actual language extension that will be capable of working with open patterns. Given such an extension and its implementation, we would like to look into how code for such patterns can be optimized without hardcoding the knowledge of the semantics of the patterns into the compiler. We would also like to experiment with other kinds of patterns (including those defined by the user), look at the interaction of patterns with both the standard library and other facilities in the language, and make views less ad-hoc." http://www.stroustrup.com/OpenPatternMatching.pdf http://www.stroustrup.com/OpenPatternMatching.pdf