This function takes an alist of the same form as
`auto-mode-alist'. It then tries to find the appropriate match
in the alist for the current buffer; setting the mode if
-possible. Returns non-`nil' if the mode was set, `nil'
-otherwise. DIR-LOCAL is a boolean which, if true, says that this
-call is via directory-locals and extra checks should be done."
+possible.
+Return non-nil if the mode was set, nil otherwise.
+DIR-LOCAL non-nil means this call is via directory-locals, and
+extra checks should be done."
(if buffer-file-name
(let (mode
(name buffer-file-name)