sound object
This method will start the sound playback and set it to loop forever.
bool play_looped()
Parameters:
None.
Return value:
true on success, false on failure.
Remarks:
This method will start the playback of the sound in a looped state, meaning that it keeps repeating until a method such as "pause" or "stop" is called, or alternatively until the object is destroyed.
Example:

    // Play a sound and loop it until the user presses space.

    void main()
    {
    sound ambience;
    ambience.load("ding.ogg");
    show_game_window("Sound Test");
    if(ambience.active==false)
    {
    alert("Error", "The sound could not be loaded.");
    exit();
    }
    ambience.play_looped();
    while(key_pressed(KEY_SPACE)==false)
    {
    wait(5);
    }
    }