Allow undoing changes while doing query-replace

* doc/lispref/searching.texi (Search and Replace): Mention
undo (bug#21684).

* lisp/replace.el (query-replace-help): Document undo.
(perform-replace): Implement undo while replacing text.

1 files changed, 5 insertions, 0 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 255afde7463..cf121d0eec3 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -435,6 +435,11 @@ is intended for adding to 'kill-emacs-query-functions'.
 in favor of the global `M-s h' bindings introduced in Emacs-23.1.
 They'll disappear soon.
 
++++
+** New bindings for 'query-replace-map'.
+`undo', undo the last replacement; bound to `u'.
+`undo-all', undo all replacements; bound to `U'.
+
 
 * Changes in Specialized Modes and Packages in Emacs 25.1