Add "union tags" in mpc.el.

* mpc.el: Remove backward compatibility code.
(mpc-browser-tags): Change default.
(mpc--find-memoize-union-tags): New var.
(mpc-cmd-flush, mpc-cmd-special-tag-p): New fun.
(mpc-cmd-find): Handle the case where the playlist does not exist.
Handle union-tags.
(mpc-cmd-list): Use mpc-cmd-special-tag-p.  Handle union-tags.
(mpc-cmd-add): Use mpc-cmd-flush.
(mpc-tagbrowser-tag-name): New fun.
(mpc-tagbrowser-buf): Use it.
(mpc-songs-refresh): Use cond.  Move to point-min as a fallback.

1 files changed, 1 insertions, 0 deletions

diff --git a/etc/NEWS b/etc/NEWS
index ce3ba7cf153..5bc053a69c7 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -45,6 +45,7 @@ Use `set-scroll-bar-mode' to change this.
 
 * Changes in Specialized Modes and Packages in Emacs 24.1
 
+** mpc.el: Can use pseudo tags of the form tag1|tag2 as a union of two tags.
 ** Customize
 
 *** Customize buffers now contain a search field.