Fix customization of debugger-print-function (Bug#29077)

* lisp/emacs-lisp/debug.el (debugger-print-function): The :options
keyword has no effect for :type 'function, use :type '(choice ...)
instead.

diff --git a/lisp/emacs-lisp/debug.el b/lisp/emacs-lisp/debug.el
index 6c754615b002470ea9d3a775e18daeb12ccf3395..e1b87b5c6e221e355339ad92855c2c1aea28841c 100644 (file)
--- a/lisp/emacs-lisp/debug.el
+++ b/lisp/emacs-lisp/debug.el
@@ -51,8 +51,9 @@ the middle is discarded, and just the beginning and end are displayed."
 
 (defcustom debugger-print-function #'cl-prin1
   "Function used to print values in the debugger backtraces."
-  :type 'function
-  :options '(cl-prin1 prin1)
+  :type '(choice (const cl-prin1)
+                 (const prin1)
+                 function)
   :version "26.1")
 
 (defcustom debugger-bury-or-kill 'bury