Add raiseFocus.

darcs-hash:20070320160135-a5988-01f4a5df331fac6fbf00c209a40105da74b9b88d

1 files changed, 7 insertions, 0 deletions

diff --git a/StackSet.hs b/StackSet.hs
index 3604f3b..8103075 100644
--- a/StackSet.hs
+++ b/StackSet.hs
@@ -162,5 +162,12 @@ delete k w = maybe w tweak (M.lookup k (cache w))
                     , stacks = M.adjust (L.delete k) i (stacks w)
                     , focus  = M.update (\k' -> if k == k' then elemAfter k (stacks w M.! i) else Just k') i (focus w) }
 
+-- | /O(log n)/. If the given window is contained in a workspace, make it the
+-- focused window of that workspace.
+raiseFocus :: Ord a => a -> StackSet a -> StackSet a
+raiseFocus k w = case M.lookup k (cache w) of
+    Nothing -> w
+    Just i  -> w { focus = M.insert i k (focus w) }
+
 elemAfter :: Eq a => a -> [a] -> Maybe a
 elemAfter w ws = listToMaybe . filter (/= w) . dropWhile (/= w) $ ws ++ ws