Play a wav file with Haskell

Question

Is there a simple, direct way to play a WAV file from Haskell using some library and possibly such that I play many sounds at once?

I'm aware of OpenAL but I'm not writing some advanced audio synthesis program, I just want to play some sounds for a little play thing. Ideally the API might be something like:

readWavFile :: FilePath -> IO Wave
playWave :: Wave -> IO ()
playWaveNonBlocking :: Wave -> IO ()

I'm this close to merely launching mplayer or something. Or trying to cat the wav directly to /dev/snd/ or somesuch.

Answer 1

This is how to play multiple sounds on multiple channels at once with SDL. I think this answers the question criteria. WAV files, simple, Haskell, multiple channels.

import Control.Monad
import Control.Monad.Fix
import Graphics.UI.SDL as SDL
import Graphics.UI.SDL.Mixer as Mix

main = do
  SDL.init [SDL.InitAudio]
  result <- openAudio audioRate audioFormat audioChannels audioBuffers
  classicJungle <- Mix.loadWAV "/home/chris/Samples/ClassicJungle/A4.wav"
  realTech      <- Mix.loadWAV "/home/chris/Samples/RealTech/A4.wav"
  ch1 <- Mix.playChannel anyChannel classicJungle 0
  SDL.delay 1000
  ch2 <- Mix.playChannel anyChannel realTech 0
  fix $ \loop -> do
    SDL.delay 50
    stillPlaying <- numChannelsPlaying
    when (stillPlaying /= 0) loop
  Mix.closeAudio
  SDL.quit

  where audioRate     = 22050
        audioFormat   = Mix.AudioS16LSB
        audioChannels = 2
        audioBuffers  = 4096
        anyChannel    = (-1)

Answer 2

I realize this is not actually a convenient way to do it, but I had the test code lying around, so...

{-# LANGUAGE NoImplicitPrelude #-}
module Wav (main) where

import Fay.W3C.Events
import Fay.W3C.Html5

import Language.Fay.FFI
import Language.Fay.Prelude

main :: Fay ()
main = addWindowEventListener "load" run

run :: Event -> Fay Bool
run _ = do
    aud <- mkAudio
    setSrc aud "test.wav"
    play aud
    return False


mkAudio :: Fay HTMLAudioElement
mkAudio = ffi "new Audio()"

addWindowEventListener :: String -> (Event -> Fay Bool) -> Fay ()
addWindowEventListener = ffi "window['addEventListener'](%1,%2,false)"

There you go--playing a WAV file in Haskell thanks to the power of HTML5! All you have to do is launch a web browser instead of mplayer. :D