From c99a0d31a758ee43527e7a66c9721247ebab3f86 Mon Sep 17 00:00:00 2001 From: Andrea Rossato Date: Sun, 10 Jun 2007 14:37:46 +0200 Subject: haddock compatibility darcs-hash:20070610123746-32816-e5a1b61d81fa52f608d7936f900431bd6620c3c7 --- StackSet.hs | 149 +++++++++++++++++++++++++++++++++--------------------------- 1 file changed, 81 insertions(+), 68 deletions(-) (limited to 'StackSet.hs') diff --git a/StackSet.hs b/StackSet.hs index 4b74646..619d536 100644 --- a/StackSet.hs +++ b/StackSet.hs @@ -8,9 +8,7 @@ -- Stability : experimental -- Portability : portable, Haskell 98 -- ------------------------------------------------------------------------------ --- --- ** Introduction +-- Introduction -- -- The 'StackSet' data type encodes a window manager abstraction. The -- window manager is a set of virtual workspaces. On each workspace is a @@ -18,18 +16,18 @@ -- window on each workspace has focus. The focused window on the current -- workspace is the one which will take user input. It can be visualised -- as follows: --- --- Workspace { 0*} { 1 } { 2 } { 3 } { 4 } --- --- Windows [1 [] [3* [6*] [] --- ,2*] ,4 --- ,5] --- +-- +-- > Workspace { 0*} { 1 } { 2 } { 3 } { 4 } +-- > +-- > Windows [1 [] [3* [6*] [] +-- > ,2*] ,4 +-- > ,5] +-- -- Note that workspaces are indexed from 0, windows are numbered -- uniquely. A '*' indicates the window on each workspace that has -- focus, and which workspace is current. -- --- ** Zipper +-- Zipper -- -- We encode all the focus tracking directly in the data structure, with a 'zipper': -- @@ -42,7 +40,7 @@ -- resulting data structure will share as much of its components with -- the old structure as possible. -- --- Oleg Kiselyov, 27 Apr 2005, haskell@, "Zipper as a delimited continuation" +-- Oleg Kiselyov, 27 Apr 2005, haskell\@, "Zipper as a delimited continuation" -- -- We use the zipper to keep track of the focused workspace and the -- focused window on each workspace, allowing us to have correct focus @@ -58,7 +56,7 @@ -- -- The Zipper, Haskell wikibook -- --- ** Xinerama support: +-- Xinerama support: -- -- Xinerama in X11 lets us view multiple virtual workspaces -- simultaneously. While only one will ever be in focus (i.e. will @@ -67,13 +65,14 @@ -- (viewed) on which physical screens. We use a simple Map Workspace -- Screen for this. -- --- ** Master and Focus +-- Master and Focus -- -- Each stack tracks a focused item, and for tiling purposes also tracks -- a 'master' position. The connection between 'master' and 'focus' -- needs to be well defined. Particular in relation to 'insert' and -- 'delete'. -- + module StackSet ( StackSet(..), Workspace(..), Screen(..), Stack(..), RationalRect(..), new, view, lookupWorkspace, peek, index, integrate, focusUp, focusDown, @@ -85,45 +84,60 @@ import Data.Maybe (listToMaybe) import qualified Data.List as L (delete,find,genericSplitAt) import qualified Data.Map as M (Map,insert,delete,empty) +-- | -- API changes from xmonad 0.1: -- StackSet constructor arguments changed. StackSet workspace window screen --- new, -- was: empty --- view, --- index, --- peek, -- was: peek/peekStack --- focusUp, focusDown, -- was: rotate --- swapUp, swapDown --- focus -- was: raiseFocus --- insertUp, -- was: insert/push --- delete, --- swapMaster, -- was: promote/swap --- member, --- shift, --- lookupWorkspace, -- was: workspace --- visibleWorkspaces -- gone. -- ------------------------------------------------------------------------- - +-- * new, -- was: empty +-- +-- * view, +-- +-- * index, +-- +-- * peek, -- was: peek\/peekStack +-- +-- * focusUp, focusDown, -- was: rotate +-- +-- * swapUp, swapDown +-- +-- * focus -- was: raiseFocus -- +-- * insertUp, -- was: insert\/push +-- +-- * delete, +-- +-- * swapMaster, -- was: promote\/swap +-- +-- * member, +-- +-- * shift, +-- +-- * lookupWorkspace, -- was: workspace +-- +-- * visibleWorkspaces -- gone. +-- +------------------------------------------------------------------------ +-- | -- A cursor into a non-empty list of workspaces. +-- -- We puncture the workspace list, producing a hole in the structure -- used to track the currently focused workspace. The two other lists -- that are produced are used to track those workspaces visible as -- Xinerama screens, and those workspaces not visible anywhere. --- + data StackSet i a sid = - StackSet { size :: !i -- number of workspaces - , current :: !(Screen i a sid) -- currently focused workspace - , visible :: [Screen i a sid] -- non-focused workspaces, visible in xinerama - , hidden :: [Workspace i a] -- workspaces not visible anywhere - , floating :: M.Map a RationalRect -- floating windows + StackSet { size :: !i -- ^ number of workspaces + , current :: !(Screen i a sid) -- ^ currently focused workspace + , visible :: [Screen i a sid] -- ^ non-focused workspaces, visible in xinerama + , hidden :: [Workspace i a] -- ^ workspaces not visible anywhere + , floating :: M.Map a RationalRect -- ^ floating windows } deriving (Show, Read, Eq) --- Visible workspaces, and their Xinerama screens. +-- | Visible workspaces, and their Xinerama screens. data Screen i a sid = Screen { workspace :: !(Workspace i a), screen :: !sid } deriving (Show, Read, Eq) --- +-- | -- A workspace is just a tag - its index - and a stack -- data Workspace i a = Workspace { tag :: !i, stack :: Stack a } @@ -132,21 +146,21 @@ data Workspace i a = Workspace { tag :: !i, stack :: Stack a } data RationalRect = RationalRect Rational Rational Rational Rational deriving (Show, Read, Eq) --- +-- | -- A stack is a cursor onto a (possibly empty) window list. -- The data structure tracks focus by construction, and -- the master window is by convention the top-most item. -- Focus operations will not reorder the list that results from -- flattening the cursor. The structure can be envisaged as: -- --- +-- master: < '7' > --- up | [ '2' ] --- +--------- [ '3' ] --- focus: < '4' > --- dn +----------- [ '8' ] +-- > +-- master: < '7' > +-- > up | [ '2' ] +-- > +--------- [ '3' ] +-- > focus: < '4' > +-- > dn +----------- [ '8' ] -- -- A 'Stack' can be viewed as a list with a hole punched in it to make --- the focused position. Under the zipper/calculus view of such +-- the focused position. Under the zipper\/calculus view of such -- structures, it is the differentiation of a [a], and integrating it -- back has a natural implementation used in 'index'. -- @@ -162,7 +176,7 @@ abort :: String -> a abort x = error $ "xmonad: StackSet: " ++ x -- --------------------------------------------------------------------- --- Construction +-- | Construction -- | /O(n)/. Create a new stackset, of empty stacks, of size 'n', with -- 'm' physical screens. 'm' should be less than or equal to 'n'. @@ -178,14 +192,14 @@ new n m | n > 0 && m > 0 = StackSet n cur visi unseen M.empty (cur:visi) = [ Screen i s | (i,s) <- zip seen [0..] ] -- now zip up visibles with their screen id --- --- /O(w)/. Set focus to the workspace with index 'i'. +-- | +-- /O(w)/. Set focus to the workspace with index \'i\'. -- If the index is out of range, return the original StackSet. -- -- Xinerama: If the workspace is not visible on any Xinerama screen, it -- becomes the current screen. If it is in the visible list, it becomes -- current. --- + view :: (Eq a, Eq s, Integral i) => i -> StackSet i a s -> StackSet i a s view i s | i < 0 && i >= size s || i == tag (workspace (current s)) = s -- out of bounds or current @@ -205,7 +219,7 @@ view i s -- workspace tags defined in 'new' -- --------------------------------------------------------------------- --- Xinerama operations +-- | Xinerama operations -- | Find the tag of the workspace visible on Xinerama screen 'sc'. -- Nothing if screen is out of bounds. @@ -215,7 +229,7 @@ lookupWorkspace sc w = listToMaybe [ tag i | Screen i s <- current w : visible w -- --------------------------------------------------------------------- -- Operations on the current stack --- +-- | -- The 'with' function takes a default value, a function, and a -- StackSet. If the current stack is Empty, 'with' returns the -- default value. Otherwise, it applies the function to the stack, @@ -226,28 +240,28 @@ with dflt f s = case stack (workspace (current s)) of Empty -> dflt; v -> f v -- TODO: ndm: a 'catch' proof here that 'f' only gets Node -- constructors, hence all 'f's are safe below? --- +-- | -- Apply a function, and a default value for Empty, to modify the current stack. -- modify :: Stack a -> (Stack a -> Stack a) -> StackSet i a s -> StackSet i a s modify d f s = s { current = (current s) { workspace = (workspace (current s)) { stack = with d f s }}} --- +-- | -- /O(1)/. Extract the focused element of the current stack. -- Return Just that element, or Nothing for an empty stack. -- peek :: StackSet i a s -> Maybe a peek = with Nothing (return . focus) --- +-- | -- /O(n)/. Flatten a Stack into a list. -- integrate :: Stack a -> [a] integrate Empty = [] integrate (Node x l r) = reverse l ++ x : r --- +-- | -- /O(s)/. Extract the stack on the current workspace, as a list. -- The order of the stack is determined by the master window -- it will be -- the head of the list. The implementation is given by the natural @@ -258,7 +272,7 @@ index = with [] integrate -- let is = t : r ++ reverse l in take (length is) (dropWhile (/= m) (cycle is)) --- +-- | -- /O(1), O(w) on the wrapping case/. -- -- focusUp, focusDown. Move the window focus up or down the stack, @@ -284,7 +298,7 @@ focusUp' (Node t [] rs) = Node x xs [] where (x:xs) = reverse (t:rs) swapUp' (Node t (l:ls) rs) = Node t ls (l:rs) swapUp' (Node t [] rs) = Node t (reverse rs) [] --- reverse a stack: up becomes down and down becomes up. +-- | reverse a stack: up becomes down and down becomes up. reverseStack :: Stack a -> Stack a reverseStack (Node t ls rs) = Node t rs ls reverseStack x = x @@ -299,7 +313,7 @@ focusWindow w s | Just w == peek s = s n <- findIndex w s return $ until ((Just w ==) . peek) focusUp (view n s) --- +-- | -- Finding if a window is in the stackset is a little tedious. We could -- keep a cache :: Map a i, but with more bookkeeping. -- @@ -318,9 +332,9 @@ findIndex a s = listToMaybe has x (Node t l r) = x `elem` (t : l ++ r) -- --------------------------------------------------------------------- --- Modifying the stackset +-- | Modifying the stackset --- +-- | -- /O(n)/. (Complexity due to duplicate check). Insert a new element into -- the stack, above the currently focused element. -- @@ -343,7 +357,7 @@ insertUp a s = if member a s then s else insert -- Old semantics, from Huet. -- > w { down = a : down w } --- +-- | -- /O(1) on current window, O(n) in general/. Delete window 'w' if it exists. -- There are 4 cases to consider: -- @@ -385,8 +399,8 @@ sink :: Ord a => a -> StackSet i a s -> StackSet i a s sink w s = s { floating = M.delete w (floating s) } ------------------------------------------------------------------------ --- Setting the master window - +-- | Setting the master window +-- -- /O(s)/. Set the master window to the focused window. -- The old master window is swapped in the tiling order with the focused window. -- Focus stays with the item moved. @@ -395,12 +409,11 @@ swapMaster = modify Empty $ \c -> case c of Node _ [] _ -> c -- already master. Node t ls rs -> Node t [] (ys ++ x : rs) where (x:ys) = reverse ls - -- natural! keep focus, move current to the top, move top to current. - +-- natural! keep focus, move current to the top, move top to current. +-- -- --------------------------------------------------------------------- --- Composite operations +-- | Composite operations -- - -- /O(w)/. shift. Move the focused element of the current stack to stack -- 'n', leaving it as the focused element on that stack. The item is -- inserted above the currently focused element on that workspace. -- @@ -411,4 +424,4 @@ shift :: (Ord a, Eq s, Integral i) => i -> StackSet i a s -> StackSet i a s shift n s = if and [n >= 0,n < size s,n /= tag (workspace (current s))] then maybe s go (peek s) else s where go w = foldr ($) s [view (tag (workspace (current s))),insertUp w,view n,delete w] - -- ^^ poor man's state monad :-) + -- ^^ poor man's state monad :-) -- cgit v1.2.3