file-name-sans-versions

file-name-sans-versions is a compiled Lisp function in `files.el'.

(file-name-sans-versions NAME &optional KEEP-BACKUP-VERSION)

Return file NAME sans backup versions or strings.
This is a separate procedure so your site-init or startup file can
redefine it.
If the optional argument KEEP-BACKUP-VERSION is non-nil,
we do not remove backup version numbers, only true file version numbers.
See also `file-name-version-regexp'.