Работающая версия audioread

wave.hs

@@ -1,15 +1,31 @@
 -- Создан:  Ср 28 сен 2016 10:18:53
--- Изменен: Чт 29 сен 2016 09:53:59
+-- Изменен: Чт 29 сен 2016 11:18:07
 
-import Data.List
+import System.Environment
 import Data.WAVE
+-- import Data.List
 
-n = 48000
+--Выбор канала из пары
+chL :: [a] -> a
+chL pair = pair!!0
 
-chL (l:r) = l
-chR (l:r) = r
+chR :: [a] -> a
+chR pair = pair!!1
 
+audioread :: String -> String -> [Char] -> IO ()
+audioread samples file ch = do
+	w <- getWAVEFile file
+	mapM_ print (map (sampleToDouble . channel) (take (read samples::Int) $ waveSamples w)) where
+		channel (xs)
+			| ch == ['R'] = chR xs
+			| ch == ['L'] = chL xs
+			| otherwise  = chL xs
+
+main :: IO ()
 main = do
-	w <- getWAVEFile "000.wav"
-	mapM_ print (map chL (take n $ waveSamples w))
+	cmd <- getArgs
+	case cmd of
+	  [samples, file, ch] -> audioread samples file ch
+	  [samples, file]     -> audioread samples file ['L']
+	  _                   -> putStrLn "Usage: audioread [samples] [file.wav] [L/R]"