2 files changed, 9 insertions, 1 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 99dff70118a..48eb3c9e955 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,8 @@
 2010-11-18  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+        * minibuffer.el (completion-fail-discreetly): New var.
+        (completion--do-completion): Use it.
+
         * electric.el (electric-pair-pairs): New var.
         (electric-pair-post-self-insert-function): Use it.
         (electric-layout-post-self-insert-function): Don't insert a before
diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index 0275dc1923b..78580c86e45 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -530,6 +530,9 @@ candidates than this number."
 (make-variable-buffer-local 'completion-all-sorted-completions)
 (defvar completion-cycling nil)
 
+(defvar completion-fail-discreetly nil
+  "If non-nil, stay quiet when there  is no match.")
+
 (defun completion--do-completion (&optional try-completion-function)
   "Do the completion and return a summary of what happened.
 M = completion was performed, the text was Modified.
@@ -558,7 +561,9 @@ E = after completion we now have an Exact match.
     (cond
      ((null comp)
       (minibuffer-hide-completions)
-      (ding) (minibuffer-message "No match") (minibuffer--bitset nil nil nil))
+      (unless completion-fail-discreetly
+        (ding) (minibuffer-message "No match"))
+      (minibuffer--bitset nil nil nil))
      ((eq t comp)
       (minibuffer-hide-completions)
       (goto-char (field-end))