[emms-help] make emms-player-start cycle players

[Andrea Russo]

Hi!

This patch make emms-player-start a little more "fault tolerant" by
trying all suitable players for the specified track in
`emms-player-list' until one succeeds.

This can be useful when using emms customizations in different
machines where the set of available players can vary.

I prepared a Changelog entry just in case you want to merge in the
mainstream.  If necessary I'm willing to sign legal papers to assign
copyright to the FSF.

Hope this is useful.

Thanks,
Andrea.

2006-06-16  Andrea Russo  <address@hidden>

        * emms.el (emms-player-for): Returns a list of players that can
        play the passed track instead of returning the first one.
        (emms-player-start): Now it cycles through a list of players until
        one starts without errors.

--- old-emms2/emms.el   2006-06-16 19:43:25.000000000 +0200
+++ new-emms2/emms.el   2006-06-16 19:43:25.000000000 +0200
@@ -1218,27 +1218,33 @@
   "Return an EMMS player capable of playing TRACK.
 This will be the first player whose PLAYABLEP function returns non-nil,
 or nil if no such player exists."
-  (let ((lis emms-player-list))
-    (while (and lis
-                (not (funcall (emms-player-get (car lis) 'playablep)
-                              track)))
+  (let ((lis emms-player-list)
+       players)
+    (while lis
+      (if (funcall (emms-player-get (car lis) 'playablep)
+                  track)
+         (add-to-list 'players (car lis) t))
       (setq lis (cdr lis)))
-    (if lis
-        (car lis)
-      nil)))
+    players))
 
 (defun emms-player-start (track)
   "Start playing TRACK."
   (if emms-player-playing-p
       (error "A player is already playing")
-    (let ((player (emms-player-for track)))
-      (if (not player)
+    (let ((players (emms-player-for track)))
+      (if (not players)
           (error "Don't know how to play track: %S" track)
         ;; Change default-directory so we don't accidentally block any
         ;; directories the current buffer was visiting.
-        (let ((default-directory "/"))
-          (funcall (emms-player-get player 'start)
-                   track))))))
+       (let ((default-directory "/")
+             (problems t))
+         (while problems
+           (condition-case err
+               (progn
+                 (funcall (emms-player-get (car players) 'start)
+                          track)
+                 (setq problems nil))
+             (file-error (setq players (cdr players))))))))))
 
 (defun emms-player-started (player)
   "Declare that the given EMMS PLAYER has started.

-- 
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