FocusNth initial import

FocusNth.hs

@@ -0,0 +1,42 @@
+-----------------------------------------------------------------------------
+-- |
+-- Module       : XMonadContrib.FocusNth
+-- Copyright    : (c) Karsten Schoelzel <kuser@gmx.de>
+-- License      : BSD
+--
+-- Maintainer   : Karsten Schoelzel <kuser@gmx.de>
+-- Stability    : unstable
+-- Portability  : unportable
+--
+-- Focus the n'th window on the screen.
+-----------------------------------------------------------------------------
+
+module XMonadContrib.FocusNth (
+                 -- * Usage
+                 -- $usage
+                 focusNth) where
+
+import StackSet
+import Operations
+import XMonad
+
+-- $usage
+-- > import XMonadContrib.FocusNth
+
+-- > -- mod4-[1..9] @@ Switch to window N
+-- > ++ [((mod4Mask, k), focusNth i)
+-- >     | (i, k) <- zip [0 .. 8] [xK_1 ..]]
+
+focusNth :: Int -> X ()
+focusNth = windows . modify' . focusNth'
+
+focusNth' :: Int -> Stack a -> Stack a
+focusNth' n s@(Stack _ ls rs)	| (n < 0) || (n > length(ls) + length(rs)) = s
+				| otherwise = listToStack n (integrate s)
+
+listToStack :: Int -> [a] -> Stack a
+listToStack n l = Stack t ls rs
+	where	(t:rs)	= drop n l
+		ls	= reverse (take n l)
+
+