From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Sat, 19 Mar 2005 16:36:01 +0000 (+0000)
Subject: (keys_of_keyboard): Just use `ignore' instead of the redundant `ignore-event'.
X-Git-Tag: ttn-vms-21-2-B4~1684
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=a18bf8979eefd6716b8755755781e14f86d2c8ab;p=emacs.git

(keys_of_keyboard): Just use `ignore' instead of the redundant `ignore-event'.
---

diff --git a/src/keyboard.c b/src/keyboard.c
index eb8d481dc11..f9b0a843de5 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -11427,10 +11427,29 @@ keys_of_keyboard ()
 
   initial_define_lispy_key (Vspecial_event_map, "delete-frame",
 			    "handle-delete-frame");
+  /* Here we used to use `ignore-event' which would simple set prefix-arg to
+     current-prefix-arg, as is done in `handle-switch-frame'.
+     But `handle-switch-frame is not run from the special-map.
+     Commands from that map are run in a special way that automatically
+     preserves the prefix-arg.  Restoring the prefix arg here is not just
+     redundant but harmful:
+     - C-u C-x v =
+     - current-prefix-arg is set to non-nil, prefix-arg is set to nil.
+     - after the first prompt, the exit-minibuffer-hook is run which may
+       iconify a frame and thus push a `iconify-frame' event.
+     - after running exit-minibuffer-hook, current-prefix-arg is
+       restored to the non-nil value it had before the prompt.
+     - we enter the second prompt.
+       current-prefix-arg is non-nil, prefix-arg is nil.
+     - before running the first real event, we run the special iconify-frame
+       event, but we pass the `special' arg to execute-command so
+       current-prefix-arg and prefix-arg are left untouched.
+     - here we foolishly copy the non-nil current-prefix-arg to prefix-arg.
+     - the next key event will have a spuriously non-nil current-prefix-arg.  */
   initial_define_lispy_key (Vspecial_event_map, "iconify-frame",
-			    "ignore-event");
+			    "ignore");
   initial_define_lispy_key (Vspecial_event_map, "make-frame-visible",
-			    "ignore-event");
+			    "ignore");
   /* Handling it at such a low-level causes read_key_sequence to get
    * confused because it doesn't realize that the current_buffer was
    * changed by read_char.