Quick and dirty way of selectively loading a playable audio file in HTML5

audio.js

    // Because HTML5 Audio support isn't all that consistent, we need to do something.
    // With at least both .ogg and .mp3 formats, they will play on all 5 major
    // browsers on the desktop.
    // XXX If more ancient support is desired, feel free to add <embed> support. Or Flash.
    //
    // sources should be a list of audio files of the same sound, but in different formats.
    // e.g.: ['effect.ogg', 'effect.mp3', 'effect.wav']
    // Depending on the browser capability, it will only add one of them that is playable.
    // If no compatible format is found for that browser, a warning will be issued.
    // List of Audio MIME Types:
    // http://webdesign.about.com/od/sound/a/sound_mime_type.htm
    function audio(sources) {
        var x = new Audio();
        for (var s in sources) {
            if (sources.hasOwnProperty(s)) {
                var file = sources[s];
                if ((file.endswith('.mp3') && x.canPlayType('audio/mpeg'))          ||
                    (file.endswith('.ogg') && x.canPlayType('audio/ogg'))           ||
                    (file.endswith('.mid') && x.canPlayType('audio/mid'))           ||
                    (file.endswith('.m3u') && x.canPlayType('audio/x-mpegurl'))     ||
                    (file.endswith('.ra')  && x.canPlayType('audio/x-pn-realaudio'))||
                    (file.endswith('.wav') &&
                        (x.canPlayType('audio/wav') || x.canPlayType('audio/x-wav')))
                    ) {
                    x.src = file;
                    return x;
                }
            }
        }
        // If we got to this point, there wasn't anything we can play
        console.warn('None of the audio files in ' + JSON.stringify(sources) + ' are supported.');
        return x;
    }