Minor fixes for the last change

* lisp/simple.el (delete-indentation):
* doc/emacs/indent.texi (Indentation Commands):
* etc/NEWS: Fix last change.  (Bug#34796)

3 files changed, 11 insertions, 8 deletions

diff --git a/doc/emacs/indent.texi b/doc/emacs/indent.texi
index 61cf7332b5c..5f40acba151 100644
--- a/doc/emacs/indent.texi
+++ b/doc/emacs/indent.texi
@@ -110,9 +110,9 @@ parentheses, or if the junction follows another newline.
 If there is a fill prefix, @kbd{M-^} deletes the fill prefix if it
 appears after the newline that is deleted.  @xref{Fill Prefix}.
 
-With the universal prefix argument, join the current line line to the
-following line.  With the region active, join lines in the region.  If
-both the argument is set and the region is active, the region is ignored.
+With a prefix argument, join the current line line to the following
+line.  If the region is active, and no prefix argument is given, join
+all lines in the region instead.
 
 @item C-M-\
 @kindex C-M-\
diff --git a/etc/NEWS b/etc/NEWS
index 7ebc9f29183..9f569a73673 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -370,8 +370,10 @@ region using a given replacement-function in a non-destructive manner
 arguments mitigating performance issues when operating on huge
 buffers.
 
-** The command `delete-indentation` now can operate on the active
-region
+** The command 'delete-indentation' now operates on the active region.
+If the region is active, the command joins all the lines in the
+region.  When there's no active region, the command works on the
+current and the previous or the next line, as before.
 
 +++
 
diff --git a/lisp/simple.el b/lisp/simple.el
index 7878272ec90..f52bd95bf84 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -596,9 +596,10 @@ When called from Lisp code, ARG may be a prefix string to copy."
 (defun delete-indentation (&optional arg beg end)
   "Join this line to previous and fix up whitespace at join.
 If there is a fill prefix, delete it from the beginning of this
-line.  With prefix ARG, join the current line to the following line.
-With the region active, join lines in the region. If both the
-argument is set and the region is active, the region is ignored."
+line.
+With prefix ARG, join the current line to the following line.
+If the region is active, join all the lines in the region.  (The
+region is ignored if prefix argument is given.)"
   (interactive "*P\nr")
   (if arg (forward-line 1)
     (if (use-region-p)