From fcb57bd657ec596dc3225be1d8551db2079eae40 Mon Sep 17 00:00:00 2001
From: Bogdan Sinitsyn <bogdan.sinitsyn@gmail.com>
Date: Tue, 25 Oct 2016 08:22:02 +0300
Subject: [PATCH] Move `modifyXS` to X.U.ExtensibleState

---
 XMonad/Hooks/ManageDocks.hs    | 11 ++---------
 XMonad/Util/ExtensibleState.hs |  8 ++++++++
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/XMonad/Hooks/ManageDocks.hs b/XMonad/Hooks/ManageDocks.hs
index 6e721598..d11d8110 100644
--- a/XMonad/Hooks/ManageDocks.hs
+++ b/XMonad/Hooks/ManageDocks.hs
@@ -103,20 +103,13 @@ refreshDocks = sendMessage UpdateDocks
 instance ExtensionClass StrutCache where
   initialValue = StrutCache M.empty
 
-modifyXS :: (ExtensionClass a, Eq a) => (a -> a) -> X Bool
-modifyXS f = do
-    v <- XS.get
-    case f v of
-        v' | v' == v   -> return False
-           | otherwise -> XS.put v' >> return True
-
 updateStrutCache :: Window -> [Strut] -> X Bool
 updateStrutCache w strut = do
-  modifyXS $ StrutCache . M.insert w strut . fromStrutCache
+  XS.modified $ StrutCache . M.insert w strut . fromStrutCache
 
 deleteFromStructCache :: Window -> X Bool
 deleteFromStructCache w = do
-  modifyXS $ StrutCache . M.delete w . fromStrutCache
+  XS.modified $ StrutCache . M.delete w . fromStrutCache
 
 -- | Detects if the given window is of type DOCK and if so, reveals
 --   it, but does not manage it.
diff --git a/XMonad/Util/ExtensibleState.hs b/XMonad/Util/ExtensibleState.hs
index 7fe3b0a7..7e12a12c 100644
--- a/XMonad/Util/ExtensibleState.hs
+++ b/XMonad/Util/ExtensibleState.hs
@@ -21,6 +21,7 @@ module XMonad.Util.ExtensibleState (
                               , remove
                               , get
                               , gets
+                              , modified
                               ) where
 
 import Data.Typeable (typeOf,cast)
@@ -115,3 +116,10 @@ gets = flip fmap get
 -- | Remove the value from the extensible state field that has the same type as the supplied argument
 remove :: ExtensionClass a => a -> X ()
 remove wit = modifyStateExts $ M.delete (show . typeOf $ wit)
+
+modified :: (ExtensionClass a, Eq a) => (a -> a) -> X Bool
+modified f = do
+    v <- get
+    case f v of
+        v' | v' == v   -> return False
+           | otherwise -> put v' >> return True