An efficient built-in mapcan

[gnu-emacs] / lisp / net / pop3.el

diff --git a/lisp/net/pop3.el b/lisp/net/pop3.el
index d09c1d00fad6c37f5d719ac5c25977e2e934f8e7..3964288fd2320f9cf531c5101173ffcd42dee6c7 100644 (file)
--- a/lisp/net/pop3.el
+++ b/lisp/net/pop3.el
@@ -402,8 +402,7 @@ Return non-nil if it is necessary to update the local UIDL file."
               (push uidl new))
             (decf i)))
          (pop3-uidl
-          (setq new (apply 'nconc (mapcar (lambda (elt) (list elt ctime))
-                                          pop3-uidl)))))
+          (setq new (mapcan (lambda (elt) (list elt ctime)) pop3-uidl))))
     (when new (setq mod t))
     ;; List expirable messages and delete them from the data to be saved.
     (setq ctime (when (numberp pop3-leave-mail-on-server)