Import of source files

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diff --git a/src/System/IO/Terminal/IO.hs b/src/System/IO/Terminal/IO.hs
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+{-|
+Module      : System.IO.Terminal.IO
+Copyright   : (c) UU, 2019
+License     : MIT
+Maintainer  : Tom Smeding
+Stability   : experimental
+Portability : POSIX, macOS, Windows
+
+Extra terminal management utility functions. This module basically extends
+the @ansi-terminal@ package.
+-}
+module System.IO.Terminal.IO
+    (queryTermSize
+    -- ,withWinchHandler
+    ,toAlternateScreen
+    ,fromAlternateScreen)
+    where
+
+-- import Foreign.C.Types
+import qualified System.Console.Terminal.Size as TS
+-- import System.Exit
+import System.IO
+-- import System.Posix.Signals
+
+
+-- sigWINCH :: CInt
+-- sigWINCH = 28
+
+
+-- | Request the current terminal size from the terminal. Probably not very
+-- fast.
+queryTermSize :: IO (Int, Int)
+queryTermSize = TS.size >>= \case
+    Just win -> return (TS.width win, TS.height win)
+    Nothing  -> error "Cannot get terminal size"
+
+-- withWinchHandler :: IO () -> IO a -> IO a
+-- withWinchHandler h act = do
+--     prevh <- installHandler sigWINCH (Catch h) Nothing
+--     case prevh of
+--         Default -> return ()
+--         Ignore -> return ()
+--         _ -> die "ERROR: A signal handler was already installed for the WINCH signal!"
+
+--     res <- act
+
+--     _ <- installHandler sigWINCH prevh Nothing
+--     return res
+
+-- | Switch to the \"alternate screen\", if the terminal supports it.
+toAlternateScreen :: IO ()
+toAlternateScreen = putStr "\x1B[?1049h" >> hFlush stdout
+
+-- | Switch from the \"alternate screen\" back to the normal buffer, if the
+-- terminal supports it.
+fromAlternateScreen :: IO ()
+fromAlternateScreen = putStr "\x1B[?1049l" >> hFlush stdout