Enable logging of state changes to stdout

Config.hs

@@ -99,6 +99,13 @@ defaultLayouts = [ tiled , mirror tiled , full ]
      -- Percent of screen to increment by when resizing panes
      delta   = 3%100
 
+--
+-- Enable logging of state changes to stdout.
+-- The internal state of the window manager is 'shown' in Haskell data format
+--
+logging :: Bool
+logging = False
+
 --
 -- The key bindings list.
 -- 

Config.hs-boot

@@ -1,3 +1,4 @@
 module Config where
 import Graphics.X11.Xlib.Types (Dimension)
 borderWidth :: Dimension
+logging     :: Bool

Main.hs

@@ -45,6 +45,7 @@ main = do
     xinesc <- getScreenInfo dpy
     nbc    <- initcolor normalBorderColor
     fbc    <- initcolor focusedBorderColor
+    hSetBuffering stdout NoBuffering
     args <- getArgs
 
     let winset | ("--resume" : s : _) <- args
@@ -89,7 +90,7 @@ main = do
                       , w  <- W.integrate (W.stack wk) ]
 
             mapM_ manage ws -- find new windows
-            -- withWindowSet (io . hPrint stderr) -- uncomment for state logging
+            when logging $ withWindowSet (io . hPrint stdout)
 
             -- main loop, for all you HOF/recursion fans out there.
             forever $ handle =<< io (nextEvent dpy e >> getEvent e)

Operations.hs

@@ -15,7 +15,7 @@ module Operations where
 
 import XMonad
 import qualified StackSet as W
-import {-# SOURCE #-} Config (borderWidth)
+import {-# SOURCE #-} Config (borderWidth,logging)
 
 import Data.Maybe
 import Data.List            (genericIndex, intersectBy, partition, delete)
@@ -168,8 +168,8 @@ windows f = do
         io $ restackWindows d (flt ++ tiled')
 
     setTopFocus
-    -- withWindowSet (io . hPrint stderr) -- logging state changes!
-    -- io performGC -- really helps 
+    when logging $ withWindowSet (io . hPrint stdout)
+    -- io performGC -- really helps, but seems to trigger GC bugs?
 
     -- We now go to some effort to compute the minimal set of windows to hide.
     -- The minimal set being only those windows which weren't previously hidden,