|index||The index of the sound to check the existence of.|
This function returns whether a sound exists (true) or
not (false). Note that if the index you search for has not
been initialised previously, this function will cause an error as
it is searching for non-existent asset indices. The sound to check
can either be a single instance of a sound (the index for
individual sounds being played can be stored in a variable when
using the audio_play_sound or audio_play_sound_at
functions) or a sound asset.
The above code checks to see if a sound exists. If it does it is set to play in a loop.