Comment 2 for bug 387470

That indeed sounds reasonable. In fact, up to now I wasn't aware of the renames feature of pytagsfs - pretty cool stuff. :-) However I'm afraid this makes my suggestion impossible to implement in a consistent manner, since in theory you could, for example, have fancy cases such as a name appearing both as composer and artist, so there would be no way to deterministically decide what the user did mean.

Still, I find this very sad, because pytagsfs is extremely useful even if you use it only "in one direction", i.e. mounting read-only, in which case the above doesn't harm. What about allowing slashes inside conditions if the -r option is set? Would this be easy to implement?
At least, I think pytagsfs shouldn't throw a SyntaxError but display a short explanation about what's going on, to preserve the user from checking his format string again and again.

kind regards,
Michael