Something that every Emacser knows is that learning Emacs is a lifelong journey. Even after years of use, we’re always discovering something new. Marcin ‘mbork’ Borkowski is always discovering new things and, happily, sharing them with the rest of us.
His latest discovery actually is something new. So new it hasn’t been officially released yet. Borkowski, being more courageous than I, doesn’t bother with releases; he simply compiles Master every once in while. The discovery is that the interactive declaration can now take extra arguments that specify which modes the function is valid for.
Functions with such a declaration appear in the describe-mode listing for any of the specified modes and it’s easy to arrange for the function not to be considered for completion when not in one of the specified modes.
Head on over to Borkowski’s post for the full story. He says that it should be in 27.2 but as far as I can tell, it isn’t. It looks as if it will be a helpful addition to the Emacs toolset.