(read-regexp): Return empty string when `default-value' is nil.

(keep-lines-read-args): Don't use empty string as the
default value for `read-regexp'.  (Bug#2495)

1 files changed, 2 insertions, 2 deletions

diff --git a/lisp/replace.el b/lisp/replace.el
index a375c87e74f..c69b4cd3c2b 100644
--- a/lisp/replace.el
+++ b/lisp/replace.el
@@ -556,7 +556,7 @@ regexp, the last isearch string, and the last replacement regexp."
              (format "%s: " prompt))
            nil nil nil 'regexp-history defaults t)))
     (if (equal input "")
-        default-value
+        (or default-value input)
       (prog1 input
         (add-to-history 'regexp-history input)))))
 
@@ -570,7 +570,7 @@ regexp, the last isearch string, and the last replacement regexp."
   "Read arguments for `keep-lines' and friends.
 Prompt for a regexp with PROMPT.
 Value is a list, (REGEXP)."
-  (list (read-regexp prompt "") nil nil t))
+  (list (read-regexp prompt) nil nil t))
 
 (defun keep-lines (regexp &optional rstart rend interactive)
   "Delete all lines except those containing matches for REGEXP.