There is no common code yet, but it's reasonable to have that. The problematic bit is that different platforms have to join the hash values in different ways - for instance OpenBSD has to have `-flag=value` but other platforms may format that like `-flag value`. It would be a good idea, but just hasn't been implemented yet.

(Perhaps `join_options` could take a separator field and including classes could set that as ` ` or `=` ?)