I have this functionality in my Forths for a long time but with the name R>DROP. I think that is a better name. There are no other names that directly manipulate the return stack like rdup, rswap. The existing words move items to and from the return and data stack R>DROP also communicates this. I certainly did not invent R>DROP so there are also other systems using this. I have now stopped using R>DROP and put back the space! My compilers produce the same code in both cases.
