From 7a3835caf1bd5cea6cd10900068f266058cb12ea Mon Sep 17 00:00:00 2001 From: Don Stewart Date: Wed, 11 Apr 2007 08:04:56 +0200 Subject: Statically distinguish Workspace and Screen indices darcs-hash:20070411060456-9c5c1-a5642813cffe434e60310d21497217ef3704b296 --- StackSet.hs | 77 ++++++++++++++++++++++++++++++++++++------------------------- 1 file changed, 45 insertions(+), 32 deletions(-) (limited to 'StackSet.hs') diff --git a/StackSet.hs b/StackSet.hs index 6bc2e99..58cbac6 100644 --- a/StackSet.hs +++ b/StackSet.hs @@ -22,7 +22,7 @@ module StackSet where import Data.Maybe -import qualified Data.List as L (delete) +import qualified Data.List as L (delete,genericLength) import qualified Data.Map as M ------------------------------------------------------------------------ @@ -35,14 +35,20 @@ import qualified Data.Map as M -- | The StackSet data structure. A table of stacks, with a current pointer data StackSet a = StackSet - { current :: !Int -- ^ the currently visible stack - , ws2screen:: !(M.Map Int Int) -- ^ workspace -> screen map - , screen2ws:: !(M.Map Int Int) -- ^ screen -> workspace - , stacks :: !(M.Map Int [a]) -- ^ the separate stacks - , focus :: !(M.Map Int a) -- ^ the window focused in each stack - , cache :: !(M.Map a Int) -- ^ a cache of windows back to their stacks + { current :: !WorkspaceId -- ^ the currently visible stack + , screen2ws:: !(M.Map ScreenId WorkspaceId) -- ^ screen -> workspace + , ws2screen:: !(M.Map WorkspaceId ScreenId) -- ^ workspace -> screen map + , stacks :: !(M.Map WorkspaceId [a]) -- ^ the separate stacks + , focus :: !(M.Map WorkspaceId a) -- ^ the window focused in each stack + , cache :: !(M.Map a WorkspaceId) -- ^ a cache of windows back to their stacks } deriving Eq +-- | Physical screen indicies +newtype ScreenId = S Int deriving (Eq,Ord,Show,Enum,Num,Integral,Real) + +-- | Virtual workspace indicies +newtype WorkspaceId = W Int deriving (Eq,Ord,Show,Enum,Num,Integral,Real) + instance Show a => Show (StackSet a) where showsPrec p s r = showsPrec p (show . toList $ s) r @@ -57,19 +63,23 @@ instance Show a => Show (StackSet a) where -- screens. (also indexed from 0) The 0-indexed stack will be current. empty :: Int -> Int -> StackSet a empty n m = StackSet { current = 0 - , ws2screen = wsScreenAssn - , screen2ws = wsScreenAssn - , stacks = M.fromList (zip [0..n-1] (repeat [])) + , screen2ws = wsScrs2Works + + , ws2screen = wsWorks2Scrs + , stacks = M.fromList (zip [0..W n-1] (repeat [])) , focus = M.empty , cache = M.empty } - where wsScreenAssn = M.fromList $ map (\x -> (x,x)) [0..m-1] - + + where (scrs,wrks) = unzip $ map (\x -> (S x, W x)) [0..m-1] + wsScrs2Works = M.fromList (zip scrs wrks) + wsWorks2Scrs = M.fromList (zip wrks scrs) + -- | /O(log w)/. True if x is somewhere in the StackSet member :: Ord a => a -> StackSet a -> Bool member a w = M.member a (cache w) --- | /O(log n)/. Looks up the stack that x is in, if it is in the StackSet -lookup :: (Monad m, Ord a) => a -> StackSet a -> m Int +-- | /O(log n)/. Looks up the workspace that x is in, if it is in the StackSet +lookup :: (Monad m, Ord a) => a -> StackSet a -> m WorkspaceId lookup x w = M.lookup x (cache w) -- | /O(n)/. Number of stacks @@ -80,10 +90,11 @@ size = M.size . stacks -- | fromList. Build a new StackSet from a list of list of elements -- If there are duplicates in the list, the last occurence wins. -fromList :: Ord a => (Int,Int,[[a]]) -> StackSet a -fromList (_,_,[]) = error "Cannot build a StackSet from an empty list" +-- FIXME: This always makes a StackSet with 1 screen. +fromList :: Ord a => (Int,[[a]]) -> StackSet a +fromList (_,[]) = error "Cannot build a StackSet from an empty list" -fromList (n,m,xs) | n < 0 || n >= length xs +fromList (n,xs) | n < 0 || n >= length xs = error $ "Cursor index is out of range: " ++ show (n, length xs) | m < 1 || m > length xs = error $ "Can't have more screens than workspaces: " ++ show (m, length xs) @@ -93,8 +104,8 @@ fromList (o,m,xs) = view o $ foldr (\(i,ys) s -> (empty (length xs) m) (zip [0..] xs) -- | toList. Flatten a stackset to a list of lists -toList :: StackSet a -> (Int,Int,[[a]]) -toList x = (current x, M.size $ screen2ws x, map snd $ M.toList (stacks x)) +toList :: StackSet a -> (Int,[[a]]) +toList x = (current x, map snd $ M.toList (stacks x)) -- | Push. Insert an element onto the top of the current stack. -- If the element is already in the current stack, it is moved to the top. @@ -110,23 +121,25 @@ peek w = peekStack (current w) w -- | /O(log s)/. Extract the element on the top of the given stack. If no such -- element exists, Nothing is returned. -peekStack :: Int -> StackSet a -> Maybe a +peekStack :: WorkspaceId -> StackSet a -> Maybe a peekStack n w = M.lookup n (focus w) -- | /O(log s)/. Index. Extract the stack at index 'n'. -- If the index is invalid, an exception is thrown. -index :: Int -> StackSet a -> [a] +index :: WorkspaceId -> StackSet a -> [a] index k w = fromJust (M.lookup k (stacks w)) --- | view. Set the stack specified by the Int argument as being visible and the +-- | view. Set the stack specified by the argument as being visible and the -- current StackSet. If the stack wasn't previously visible, it will become -- visible on the current screen. If the index is out of range an exception is -- thrown. -view :: Int -> StackSet a -> StackSet a -view n w | n >= 0 && n < M.size (stacks w) = if M.member n (ws2screen w) - then w { current = n } - else tweak (fromJust $ screen (current w) w) - | otherwise = error $ "view: index out of bounds: " ++ show n +view :: WorkspaceId -> StackSet a -> StackSet a +-- view n w | n >= 0 && n < fromIntegral (M.size (stacks w)) -- coerce + +view n w | M.member n (stacks w) + = if M.member n (ws2screen w) then w { current = n } + else tweak (fromJust $ screen (current w) w) + | otherwise = error $ "view: index out of bounds: " ++ show n where tweak sc = w { screen2ws = M.insert sc n (screen2ws w) , ws2screen = M.insert n sc (M.filter (/=sc) (ws2screen w)) @@ -134,15 +147,15 @@ view n w | n >= 0 && n < M.size (stacks w) = if M.member n (ws2screen w) } -- | That screen that workspace 'n' is visible on, if any. -screen :: Int -> StackSet a -> Maybe Int +screen :: WorkspaceId -> StackSet a -> Maybe ScreenId screen n w = M.lookup n (ws2screen w) -- | The workspace visible on screen 'sc'. Nothing if screen is out of bounds. -workspace :: Int -> StackSet a -> Maybe Int +workspace :: ScreenId -> StackSet a -> Maybe WorkspaceId workspace sc w = M.lookup sc (screen2ws w) -- | A list of the currently visible workspaces. -visibleWorkspaces :: StackSet a -> [Int] +visibleWorkspaces :: StackSet a -> [WorkspaceId] visibleWorkspaces = M.keys . ws2screen -- @@ -168,7 +181,7 @@ rotate o w = maybe w id $ do -- the top of stack 'n'. If the stack to move to is not valid, and -- exception is thrown. -- -shift :: Ord a => Int -> StackSet a -> StackSet a +shift :: Ord a => WorkspaceId -> StackSet a -> StackSet a shift n w = maybe w (\k -> insert k n (delete k w)) (peek w) -- | /O(log n)/. Insert an element onto the top of stack 'n'. @@ -176,7 +189,7 @@ shift n w = maybe w (\k -> insert k n (delete k w)) (peek w) -- If the element exists on another stack, it is removed from that stack. -- If the index is wrong an exception is thrown. -- -insert :: Ord a => a -> Int -> StackSet a -> StackSet a +insert :: Ord a => a -> WorkspaceId -> StackSet a -> StackSet a insert k n old = new { cache = M.insert k n (cache new) , stacks = M.adjust (k:) n (stacks new) , focus = M.insert n k (focus new) } -- cgit v1.2.3