* lisp/sort.el (delete-duplicate-lines): Accept an optional `keep-blanks'

argument (before the `interactive' argument).

1 files changed, 4 insertions, 2 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 42ad206699..2fe3ba79d4 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -264,10 +264,12 @@ New features include:
   name and arguments.  Useful to trace the value of (current-buffer) or
   (point) when the function is invoked.
 
-** New command `delete-duplicate-lines' has two types of operation:
-when its arg ADJACENT is non-nil (when called interactively with C-u C-u)
+** New command `delete-duplicate-lines' has new types of operation:
+When its arg ADJACENT is non-nil (when called interactively with C-u C-u)
 it works like the utility `uniq'.  Otherwise by default it deletes
 duplicate lines everywhere in the region without regard to adjacency.
+When it arg KEEP-BLANKS is non-nil (when called interactively with C-u C-u C-u),
+duplicate blank lines are preserved.
 
 ** New `cycle-spacing' command allows cycling between having just one
 space, no spaces, or reverting to the original spacing.  Like