inversion-require-emacs

inversion-require-emacs is an autoloaded compiled Lisp function in `inversion.el'.

(inversion-require-emacs EMACS-VER XEMACS-VER SXEMACS-VER)

Declare that you need either EMACS-VER, XEMACS-VER or SXEMACS-ver.
Only checks one based on which kind of Emacs is being run.