"Easy" to do if you are willing to put up with macros:

   https://github.com/gpderetta/libtask/blob/master/tests/q_test.cpp#L160

Note the macro is $, tup is just a C++ function. It doesn't handle your .bar case, but would be very easy to extend tup to handle initializer lists.

(No, I do not use it in production, it is mostly a fun curiosity, but yes, I wish lightweight named tuples were part of the language).