Use a named function for 'safe-local-variable

This improves the help screen for `version-control' (Bug#25431).

* lisp/files.el (version-control-safe-local-p): New function.
(version-control): Use it.

1 files changed, 6 insertions, 1 deletions

diff --git a/lisp/files.el b/lisp/files.el
index 0a023a88b10..b4872e46b01 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -279,8 +279,13 @@ The value `never' means do not make them."
                  (const :tag "If existing" nil)
                  (other :tag "Always" t))
   :group 'backup)
+
+(defun version-control-safe-local-p (x)
+  "Return whether X is safe as local value for `version-control'."
+  (or (booleanp x) (equal x 'never)))
+
 (put 'version-control 'safe-local-variable
-     (lambda (x) (or (booleanp x) (equal x 'never))))
+     #'version-control-safe-local-p)
 
 (defcustom dired-kept-versions 2
   "When cleaning directory, number of versions to keep."