Mention undo-amalgamate-change-group in the lispref manual

* doc/lispref/text.texi (Atomic Changes): Mention
undo-amalgamate-change-group (bug#42303).

(cherry picked from commit ba25a82855a2c03c25fec83f3056c166b692e94f)

diff --git a/doc/lispref/text.texi b/doc/lispref/text.texi
index 06975f76706c05dfe69fac6a4fdde85df2ecb535..5eead42031db3cff7238860efe84fc0d87c4e4ad 100644 (file)
--- a/doc/lispref/text.texi
+++ b/doc/lispref/text.texi
@@ -5559,6 +5559,11 @@ This function accepts all the changes in the change group specified by
 @defun cancel-change-group handle
 This function cancels and undoes all the changes in the change group
 specified by @var{handle}.
+@end defun
+
+@defun undo-amalgamate-change-group
+Amalgamate changes in change-group since @var{handle}.  I.e., remove
+all undo boundaries between the state of @var{handle} and now.
 @end defun
 
   Your code should use @code{unwind-protect} to make sure the group is