[emms-help] emms + mpd: mapcan and broken cache

[Mark Oteiza]

Hi,

I have encountered a couple problems with emms and mpd. I am using the
following:

 * mpd 0.18.6
 * emacs 24.3.50 (git master 2014-01-06)
 * emms (git master 2013-10-16)

First, 78c9cc4 introduced "mapcan" into a runtime function in
emms-player-mpd.el:

 emms-player-mpd.el:1299:1:Warning: the function `mapcan' is not known
     to be defined.

This results in (void-function mapcan).

Second, the emms cache is off by one almost everywhere. Below I put just
the head and tail of the cache.  It looks like the first mistake (in the
tail, it looks like emms does some kind of reverse sort) is when there
is a subdirectory.

;;; .emms-cache -*- mode: emacs-lisp; coding: utf-8; -*-
(puthash "Yes (2002) In A Word [V0]/CD5/10 In The Presence Of (I. Deeper, II. 
Death Of Ego, III. True Beginner, IV. Turn Around And Remember).mp3" '(*track* 
(type . file) (name . "Yes (2002) In A Word [V0]/CD5/10 In The Presence Of (I. 
Deeper, II. Death Of Ego, III. True Beginner, IV. Turn Around And 
Remember).mp3") (info-genre . "Progressive Rock") (info-year . "2002") 
(info-tracknumber . "09") (info-album . "In a Word - Disc 5") (info-title . 
"Last Train") (info-artist . "Yes") (info-playing-time . 144)) emms-cache-db)
(puthash "Yes (2002) In A Word [V0]/CD5/09 Last Train.mp3" '(*track* (type . 
file) (name . "Yes (2002) In A Word [V0]/CD5/09 Last Train.mp3") (info-genre . 
"Progressive Rock") (info-year . "2002") (info-tracknumber . "08") (info-album 
. "In a Word - Disc 5") (info-title . "The Messenger") (info-artist . "Yes") 
(info-playing-time . 315)) emms-cache-db)
;; SNIP
(puthash "Aaliyah (2001) Aaliyah [FLAC]/02 - Loose Rap (feat. Static).flac" 
'(*track* (type . file) (name . "Aaliyah (2001) Aaliyah [FLAC]/02 - Loose Rap 
(feat. Static).flac") (info-genre . "R&B") (info-tracknumber . "01") (info-year 
. "2004") (info-album . "Aaliyah") (info-title . "We Need A Resolution (feat. 
Timbaland)") (info-artist . "Aaliyah") (info-playing-time . 244)) emms-cache-db)
(puthash "Aaliyah (2001) Aaliyah [FLAC]/01 - We Need A Resolution (feat. 
Timbaland).flac" '(*track* (type . file) (name . "Aaliyah (2001) Aaliyah 
[FLAC]/01 - We Need A Resolution (feat. Timbaland).flac")) emms-cache-db)
(puthash "Bachelors Of Science - The Lost Mixtape.mp2" '(*track* (type . file) 
(name . "Bachelors Of Science - The Lost Mixtape.mp2") (info-genre . "Drum & 
Bass") (info-album . "The Lost Mixtape") (info-title . "The Lost Mixtape") 
(info-playing-time . 4585)) emms-cache-db)
(puthash "Bachelors Of Science - Scientific Elements (2007).mp2" '(*track* 
(type . file) (name . "Bachelors Of Science - Scientific Elements (2007).mp2") 
(info-genre . "Drum & Bass") (info-year . "2007") (info-album . "Scientific 
Elements") (info-title . "Scientific Elements (2007)") (info-artist . 
"Bachelors Of Science") (info-playing-time . 4452)) emms-cache-db)
(puthash "Joe Garrett - Afterglow (Temple One Mix).mp3" '(*track* (type . file) 
(name . "Joe Garrett - Afterglow (Temple One Mix).mp3") (info-genre . "Trance") 
(info-tracknumber . "1/2") (info-album . "Afterglow / Paradox (Temple One 
Mixes)") (info-title . "Afterglow (Temple One Mix)") (info-artist . "Joe 
Garrett") (info-playing-time . 378)) emms-cache-db)