clipboard should still work even if interprogram-* is disabled

(clipboard-yank): When `interprogram-cut-function' is nil,
bind it to `gui-selection-value' - the default value.
(clipboard-kill-region, clipboard-kill-ring-save): When
`interprogram-paste-function' is nil, bind it to `gui-select-text' -
the default value.

1 files changed, 9 insertions, 3 deletions

diff --git a/lisp/menu-bar.el b/lisp/menu-bar.el
index 42f48c784e1..b22c1eab907 100644
--- a/lisp/menu-bar.el
+++ b/lisp/menu-bar.el
@@ -535,19 +535,25 @@
 (defun clipboard-yank ()
   "Insert the clipboard contents, or the last stretch of killed text."
   (interactive "*")
-  (let ((gui-select-enable-clipboard t))
+  (let ((gui-select-enable-clipboard t)
+        (interprogram-paste-function (or interprogram-paste-function
+                                         #'gui-selection-value)))
     (yank)))
 
 (defun clipboard-kill-ring-save (beg end &optional region)
   "Copy region to kill ring, and save in the GUI's clipboard."
   (interactive "r\np")
-  (let ((gui-select-enable-clipboard t))
+  (let ((gui-select-enable-clipboard t)
+        (interprogram-cut-function (or interprogram-cut-function
+                                       #'gui-select-text)))
     (kill-ring-save beg end region)))
 
 (defun clipboard-kill-region (beg end &optional region)
   "Kill the region, and save it in the GUI's clipboard."
   (interactive "r\np")
-  (let ((gui-select-enable-clipboard t))
+  (let ((gui-select-enable-clipboard t)
+        (interprogram-cut-function (or interprogram-cut-function
+                                       #'gui-select-text)))
     (kill-region beg end region)))
 
 (defun menu-bar-enable-clipboard ()