mirror of
https://github.com/GrammaticalFramework/gf-core.git
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Founding the newly structured GF2.0 cvs archive.
This commit is contained in:
aarne
559
src/GF/Data/Operations.hs
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559
src/GF/Data/Operations.hs
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@@ -0,0 +1,559 @@
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module Operations where
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import Char (isSpace, toUpper, isSpace, isDigit)
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import List (nub, sortBy, sort, deleteBy, nubBy)
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import Monad (liftM2)
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infixr 5 +++
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infixr 5 ++-
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infixr 5 ++++
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infixr 5 +++++
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infixl 9 !?
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-- some auxiliary GF operations. AR 19/6/1998 -- 6/2/2001
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-- Copyright (c) Aarne Ranta 1998-2000, under GNU General Public License (see GPL)
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ifNull :: b -> ([a] -> b) -> [a] -> b
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ifNull b f xs = if null xs then b else f xs
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-- the Error monad
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data Err a = Ok a | Bad String -- like Maybe type with error msgs
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deriving (Read, Show, Eq)
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instance Monad Err where
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return = Ok
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Ok a >>= f = f a
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Bad s >>= f = Bad s
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-- analogue of maybe
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err :: (String -> b) -> (a -> b) -> Err a -> b
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err d f e = case e of
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Ok a -> f a
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Bad s -> d s
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-- add msg s to Maybe failures
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maybeErr :: String -> Maybe a -> Err a
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maybeErr s = maybe (Bad s) Ok
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testErr :: Bool -> String -> Err ()
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testErr cond msg = if cond then return () else Bad msg
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errVal :: a -> Err a -> a
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errVal a = err (const a) id
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errIn :: String -> Err a -> Err a
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errIn msg = err (\s -> Bad (s ++++ "OCCURRED IN" ++++ msg)) return
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-- used for extra error reports when developing GF
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derrIn :: String -> Err a -> Err a
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derrIn m = errIn m -- id
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performOps :: [a -> Err a] -> a -> Err a
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performOps ops a = case ops of
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f:fs -> f a >>= performOps fs
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[] -> return a
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repeatUntilErr :: (a -> Bool) -> (a -> Err a) -> a -> Err a
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repeatUntilErr cond f a = if cond a then return a else f a >>= repeatUntilErr cond f
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repeatUntil :: (a -> Bool) -> (a -> a) -> a -> a
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repeatUntil cond f a = if cond a then a else repeatUntil cond f (f a)
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okError :: Err a -> a
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okError = err (error "no result Ok") id
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isNotError :: Err a -> Bool
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isNotError = err (const False) (const True)
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showBad :: Show a => String -> a -> Err b
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showBad s a = Bad (s +++ show a)
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lookupErr :: (Eq a,Show a) => a -> [(a,b)] -> Err b
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lookupErr a abs = maybeErr ("Unknown" +++ show a) (lookup a abs)
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lookupErrMsg :: (Eq a,Show a) => String -> a -> [(a,b)] -> Err b
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lookupErrMsg m a abs = maybeErr (m +++ "gave unknown" +++ show a) (lookup a abs)
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lookupDefault :: Eq a => b -> a -> [(a,b)] -> b
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lookupDefault d x l = maybe d id $ lookup x l
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updateLookupList :: Eq a => (a,b) -> [(a,b)] -> [(a,b)]
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updateLookupList ab abs = insert ab [] abs where
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insert c cc [] = cc ++ [c]
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insert (a,b) cc ((a',b'):cc') = if a == a'
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then cc ++ [(a,b)] ++ cc'
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else insert (a,b) (cc ++ [(a',b')]) cc'
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mapPairListM :: Monad m => ((a,b) -> m c) -> [(a,b)] -> m [(a,c)]
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mapPairListM f xys =
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do yy' <- mapM f xys
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return (zip (map fst xys) yy')
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mapPairsM :: Monad m => (b -> m c) -> [(a,b)] -> m [(a,c)]
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mapPairsM f xys =
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do let (xx,yy) = unzip xys
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yy' <- mapM f yy
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return (zip xx yy')
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pairM :: Monad a => (b -> a c) -> (b,b) -> a (c,c)
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pairM op (t1,t2) = liftM2 (,) (op t1) (op t2)
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-- like mapM, but continue instead of halting with Err
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mapErr :: (a -> Err b) -> [a] -> Err ([b], String)
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mapErr f xs = Ok (ys, unlines ss)
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where
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(ys,ss) = ([y | Ok y <- fxs], [s | Bad s <- fxs])
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fxs = map f xs
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-- !! with the error monad
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(!?) :: [a] -> Int -> Err a
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xs !? i = foldr (const . return) (Bad "too few elements in list") $ drop i xs
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errList :: Err [a] -> [a]
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errList = errVal []
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singleton :: a -> [a]
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singleton = (:[])
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-- checking
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checkUnique :: (Show a, Eq a) => [a] -> [String]
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checkUnique ss = ["overloaded" +++ show s | s <- nub overloads] where
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overloads = filter overloaded ss
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overloaded s = length (filter (==s) ss) > 1
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titleIfNeeded :: a -> [a] -> [a]
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titleIfNeeded a [] = []
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titleIfNeeded a as = a:as
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errMsg :: Err a -> [String]
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errMsg (Bad m) = [m]
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errMsg _ = []
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errAndMsg :: Err a -> Err (a,[String])
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errAndMsg (Bad m) = Bad m
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errAndMsg (Ok a) = return (a,[])
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-- a three-valued maybe type to express indirections
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data Perhaps a b = Yes a | May b | Nope deriving (Show,Read,Eq,Ord)
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yes = Yes
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may = May
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nope = Nope
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mapP :: (a -> c) -> Perhaps a b -> Perhaps c b
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mapP f p = case p of
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Yes a -> Yes (f a)
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May b -> May b
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Nope -> Nope
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-- this is what happens when matching two values in the same module
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unifPerhaps :: Perhaps a b -> Perhaps a b -> Err (Perhaps a b)
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unifPerhaps p1 p2 = case (p1,p2) of
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(Nope, _) -> return p2
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(_, Nope) -> return p1
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_ -> Bad "update conflict"
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-- this is what happens when updating a module extension
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updatePerhaps :: b -> Perhaps a b -> Perhaps a b -> Err (Perhaps a b)
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updatePerhaps old p1 p2 = case (p1,p2) of
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(Yes a, Nope) -> return $ may old
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(May older,Nope) -> return $ may older
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(_, May a) -> Bad "strange indirection"
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_ -> unifPerhaps p1 p2
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-- binary search trees
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data BinTree a = NT | BT a (BinTree a) (BinTree a) deriving (Show,Read)
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isInBinTree :: (Ord a) => a -> BinTree a -> Bool
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isInBinTree x tree = case tree of
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NT -> False
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BT a left right
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| x < a -> isInBinTree x left
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| x > a -> isInBinTree x right
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| x == a -> True
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-- quick method to see if two trees have common elements
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-- the complexity is O(log |old|, |new|) so the heuristic is that new is smaller
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commonsInTree :: (Ord a) => BinTree (a,b) -> BinTree (a,b) -> [(a,(b,b))]
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commonsInTree old new = foldr inOld [] new' where
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new' = tree2list new
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inOld (x,v) xs = case justLookupTree x old of
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Ok v' -> (x,(v',v)) : xs
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_ -> xs
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justLookupTree :: (Ord a) => a -> BinTree (a,b) -> Err b
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justLookupTree = lookupTree (const [])
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lookupTree :: (Ord a) => (a -> String) -> a -> BinTree (a,b) -> Err b
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lookupTree pr x tree = case tree of
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NT -> Bad ("no occurrence of element" +++ pr x)
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BT (a,b) left right
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| x < a -> lookupTree pr x left
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| x > a -> lookupTree pr x right
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| x == a -> return b
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lookupTreeEq :: (Ord a) =>
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(a -> String) -> (a -> a -> Bool) -> a -> BinTree (a,b) -> Err b
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lookupTreeEq pr eq x tree = case tree of
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NT -> Bad ("no occurrence of element equal to" +++ pr x)
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BT (a,b) left right
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| eq x a -> return b -- a weaker equality relation than ==
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| x < a -> lookupTreeEq pr eq x left
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| x > a -> lookupTreeEq pr eq x right
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lookupTreeMany :: Ord a => (a -> String) -> [BinTree (a,b)] -> a -> Err b
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lookupTreeMany pr (t:ts) x = case lookupTree pr x t of
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Ok v -> return v
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_ -> lookupTreeMany pr ts x
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lookupTreeMany pr [] x = Bad $ "failed to find" +++ pr x
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-- destructive update
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updateTree :: (Ord a) => (a,b) -> BinTree (a,b) -> BinTree (a,b)
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updateTree = updateTreeGen True
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-- destructive or not
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updateTreeGen :: (Ord a) => Bool -> (a,b) -> BinTree (a,b) -> BinTree (a,b)
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updateTreeGen destr z@(x,y) tree = case tree of
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NT -> BT z NT NT
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BT c@(a,b) left right
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| x < a -> let left' = updateTree z left in BT c left' right
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| x > a -> let right' = updateTree z right in BT c left right'
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| otherwise -> if destr
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then BT z left right -- removing the old value of a
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else tree -- retaining the old value if one exists
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updateTreeEq ::
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(Ord a) => (a -> a -> Bool) -> (a,b) -> BinTree (a,b) -> BinTree (a,b)
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updateTreeEq eq z@(x,y) tree = case tree of
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NT -> BT z NT NT
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BT c@(a,b) left right
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| eq x a -> BT (a,y) left right -- removing the old value of a
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| x < a -> let left' = updateTree z left in BT c left' right
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| x > a -> let right' = updateTree z right in BT c left right'
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updatesTree :: (Ord a) => [(a,b)] -> BinTree (a,b) -> BinTree (a,b)
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updatesTree (z:zs) tr = updateTree z t where t = updatesTree zs tr
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updatesTree [] tr = tr
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updatesTreeNondestr :: (Ord a) => [(a,b)] -> BinTree (a,b) -> BinTree (a,b)
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updatesTreeNondestr xs tr = case xs of
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(z:zs) -> updateTreeGen False z t where t = updatesTreeNondestr zs tr
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_ -> tr
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buildTree :: (Ord a) => [(a,b)] -> BinTree (a,b)
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buildTree = sorted2tree . sortBy fs where
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fs (x,_) (y,_)
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| x < y = LT
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| x > y = GT
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| True = EQ
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-- buildTree zz = updatesTree zz NT
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sorted2tree :: [(a,b)] -> BinTree (a,b)
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sorted2tree [] = NT
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sorted2tree xs = BT x (sorted2tree t1) (sorted2tree t2) where
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(t1,(x:t2)) = splitAt (length xs `div` 2) xs
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mapTree :: (a -> b) -> BinTree a -> BinTree b
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mapTree f NT = NT
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mapTree f (BT a left right) = BT (f a) (mapTree f left) (mapTree f right)
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mapMTree :: Monad m => (a -> m b) -> BinTree a -> m (BinTree b)
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mapMTree f NT = return NT
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mapMTree f (BT a left right) = do
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a' <- f a
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left' <- mapMTree f left
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right' <- mapMTree f right
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return $ BT a' left' right'
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tree2list :: BinTree a -> [a] -- inorder
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tree2list NT = []
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tree2list (BT z left right) = tree2list left ++ [z] ++ tree2list right
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depthTree :: BinTree a -> Int
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depthTree NT = 0
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depthTree (BT _ left right) = 1 + max (depthTree left) (depthTree right)
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mergeTrees :: Ord a => BinTree (a,b) -> BinTree (a,b) -> BinTree (a,[b])
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mergeTrees old new = foldr upd new' (tree2list old) where
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upd xy@(x,y) tree = case tree of
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NT -> BT (x,[y]) NT NT
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BT (a,bs) left right
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| x < a -> let left' = upd xy left in BT (a,bs) left' right
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| x > a -> let right' = upd xy right in BT (a,bs) left right'
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| otherwise -> BT (a, y:bs) left right -- adding the new value
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new' = mapTree (\ (i,d) -> (i,[d])) new
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-- parsing
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type WParser a b = [a] -> [(b,[a])] -- old Wadler style parser
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wParseResults :: WParser a b -> [a] -> [b]
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wParseResults p aa = [b | (b,[]) <- p aa]
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-- printing
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indent :: Int -> String -> String
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indent i s = replicate i ' ' ++ s
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a +++ b = a ++ " " ++ b
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a ++- "" = a
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a ++- b = a +++ b
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a ++++ b = a ++ "\n" ++ b
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a +++++ b = a ++ "\n\n" ++ b
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prUpper :: String -> String
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prUpper s = s1 ++ s2' where
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(s1,s2) = span isSpace s
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s2' = case s2 of
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c:t -> toUpper c : t
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_ -> s2
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prReplicate n s = concat (replicate n s)
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prTList t ss = case ss of
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[] -> ""
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[s] -> s
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s:ss -> s ++ t ++ prTList t ss
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prQuotedString x = "\"" ++ restoreEscapes x ++ "\""
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prParenth s = if s == "" then "" else "(" ++ s ++ ")"
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prCurly s = "{" ++ s ++ "}"
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prBracket s = "[" ++ s ++ "]"
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prArgList xx = prParenth (prTList "," xx)
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prSemicList = prTList " ; "
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prCurlyList = prCurly . prSemicList
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restoreEscapes s =
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case s of
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[] -> []
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'"' : t -> '\\' : '"' : restoreEscapes t
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'\\': t -> '\\' : '\\' : restoreEscapes t
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c : t -> c : restoreEscapes t
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numberedParagraphs :: [[String]] -> [String]
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numberedParagraphs t = case t of
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[] -> []
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p:[] -> p
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_ -> concat [(show n ++ ".") : s | (n,s) <- zip [1..] t]
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prConjList :: String -> [String] -> String
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prConjList c [] = ""
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prConjList c [s] = s
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prConjList c [s,t] = s +++ c +++ t
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prConjList c (s:tt) = s ++ "," +++ prConjList c tt
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prIfEmpty :: String -> String -> String -> String -> String
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prIfEmpty em _ _ [] = em
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prIfEmpty em nem1 nem2 s = nem1 ++ s ++ nem2
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-- Thomas Hallgren's wrap lines
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--- optWrapLines = if argFlag "wraplines" True then wrapLines 0 else id
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wrapLines n "" = ""
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wrapLines n s@(c:cs) =
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if isSpace c
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then c:wrapLines (n+1) cs
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else case lex s of
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[(w,rest)] -> if n'>=76
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then '\n':w++wrapLines l rest
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else w++wrapLines n' rest
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where n' = n+l
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l = length w
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||||
_ -> s -- give up!!
|
||||
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||||
-- LaTeX code producing functions
|
||||
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dollar s = '$' : s ++ "$"
|
||||
mbox s = "\\mbox{" ++ s ++ "}"
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||||
ital s = "{\\em" +++ s ++ "}"
|
||||
boldf s = "{\\bf" +++ s ++ "}"
|
||||
verbat s = "\\verbat!" ++ s ++ "!"
|
||||
|
||||
mkLatexFile s = begindocument +++++ s +++++ enddocument
|
||||
|
||||
begindocument =
|
||||
"\\documentclass[a4paper,11pt]{article}" ++++ -- M.F. 25/01-02
|
||||
"\\setlength{\\parskip}{2mm}" ++++
|
||||
"\\setlength{\\parindent}{0mm}" ++++
|
||||
"\\setlength{\\oddsidemargin}{0mm}" ++++
|
||||
"\\setlength{\\evensidemargin}{-2mm}" ++++
|
||||
"\\setlength{\\topmargin}{-8mm}" ++++
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||||
"\\setlength{\\textheight}{240mm}" ++++
|
||||
"\\setlength{\\textwidth}{158mm}" ++++
|
||||
"\\begin{document}\n"
|
||||
|
||||
enddocument =
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"\n\\end{document}\n"
|
||||
|
||||
sortByLongest :: [[a]] -> [[a]]
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sortByLongest = sortBy longer where
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||||
longer x y
|
||||
| x' > y' = LT
|
||||
| x' < y' = GT
|
||||
| True = EQ
|
||||
where
|
||||
x' = length x
|
||||
y' = length y
|
||||
|
||||
combinations :: [[a]] -> [[a]]
|
||||
combinations t = case t of
|
||||
[] -> [[]]
|
||||
aa:uu -> [a:u | a <- aa, u <- combinations uu]
|
||||
|
||||
mkTextFile :: String -> IO ()
|
||||
mkTextFile name = do
|
||||
s <- readFile name
|
||||
let s' = prelude name ++ "\n\n" ++ heading name ++ "\n" ++ object s
|
||||
writeFile (name ++ ".hs") s'
|
||||
where
|
||||
prelude name = "module " ++ name ++ " where"
|
||||
heading name = "txt" ++ name ++ " ="
|
||||
object s = mk s ++ " \"\""
|
||||
mk s = unlines [" \"" ++ escs line ++ "\" ++ \"\\n\" ++" | line <- lines s]
|
||||
escs s = case s of
|
||||
c:cs | elem c "\"\\" -> '\\' : c : escs cs
|
||||
c:cs -> c : escs cs
|
||||
_ -> s
|
||||
|
||||
initFilePath :: FilePath -> FilePath
|
||||
initFilePath f = reverse (dropWhile (/='/') (reverse f))
|
||||
|
||||
-- topological sorting with test of cyclicity
|
||||
|
||||
topoTest :: Eq a => [(a,[a])] -> Either [a] [[a]]
|
||||
topoTest g = if length g' == length g then Left g' else Right (cyclesIn g ++[[]])
|
||||
where
|
||||
g' = topoSort g
|
||||
|
||||
cyclesIn :: Eq a => [(a,[a])] -> [[a]]
|
||||
cyclesIn deps = nubb $ clean $ filt $ iterFix findDep immediate where
|
||||
immediate = [[y,x] | (x,xs) <- deps, y <- xs]
|
||||
findDep chains = [y:x:chain |
|
||||
x:chain <- chains, (x',xs) <- deps, x' == x, y <- xs,
|
||||
notElem y (init chain)]
|
||||
|
||||
clean = map remdup
|
||||
nubb = nubBy (\x y -> y == reverse x)
|
||||
filt = filter (\xs -> last xs == head xs)
|
||||
remdup (x:xs) = x : remdup xs' where xs' = dropWhile (==x) xs
|
||||
remdup [] = []
|
||||
|
||||
|
||||
|
||||
topoSort :: Eq a => [(a,[a])] -> [a]
|
||||
topoSort g = reverse $ tsort 0 [ffs | ffs@(f,_) <- g, inDeg f == 0] [] where
|
||||
tsort _ [] r = r
|
||||
tsort k (ffs@(f,fs) : cs) r
|
||||
| elem f r = tsort k cs r
|
||||
| k > lx = r
|
||||
| otherwise = tsort (k+1) cs (f : tsort (k+1) (info fs) r)
|
||||
info hs = [(f,fs) | (f,fs) <- g, elem f hs]
|
||||
inDeg f = length [t | (h,hs) <- g, t <- hs, t == f]
|
||||
lx = length g
|
||||
|
||||
-- the generic fix point iterator
|
||||
|
||||
iterFix :: Eq a => ([a] -> [a]) -> [a] -> [a]
|
||||
iterFix more start = iter start start
|
||||
where
|
||||
iter old new = if (null new')
|
||||
then old
|
||||
else iter (new' ++ old) new'
|
||||
where
|
||||
new' = filter (`notElem` old) (more new)
|
||||
|
||||
-- association lists
|
||||
|
||||
updateAssoc :: Eq a => (a,b) -> [(a,b)] -> [(a,b)]
|
||||
updateAssoc ab@(a,b) as = case as of
|
||||
(x,y): xs | x == a -> (a,b):xs
|
||||
xy : xs -> xy : updateAssoc ab xs
|
||||
[] -> [ab]
|
||||
|
||||
removeAssoc :: Eq a => a -> [(a,b)] -> [(a,b)]
|
||||
removeAssoc a = filter ((/=a) . fst)
|
||||
|
||||
-- chop into separator-separated parts
|
||||
|
||||
chunks :: String -> [String] -> [[String]]
|
||||
chunks sep ws = case span (/= sep) ws of
|
||||
(a,_:b) -> a : bs where bs = chunks sep b
|
||||
(a, []) -> if null a then [] else [a]
|
||||
|
||||
readIntArg :: String -> Int
|
||||
readIntArg n = if (not (null n) && all isDigit n) then read n else 0
|
||||
|
||||
|
||||
-- state monad with error; from Agda 6/11/2001
|
||||
|
||||
newtype STM s a = STM (s -> Err (a,s))
|
||||
|
||||
appSTM :: STM s a -> s -> Err (a,s)
|
||||
appSTM (STM f) s = f s
|
||||
|
||||
stm :: (s -> Err (a,s)) -> STM s a
|
||||
stm = STM
|
||||
|
||||
stmr :: (s -> (a,s)) -> STM s a
|
||||
stmr f = stm (\s -> return (f s))
|
||||
|
||||
instance Monad (STM s) where
|
||||
return a = STM (\s -> return (a,s))
|
||||
STM c >>= f = STM (\s -> do
|
||||
(x,s') <- c s
|
||||
let STM f' = f x
|
||||
f' s')
|
||||
|
||||
readSTM :: STM s s
|
||||
readSTM = stmr (\s -> (s,s))
|
||||
|
||||
updateSTM :: (s -> s) -> STM s ()
|
||||
updateSTM f = stmr (\s -> ((),f s))
|
||||
|
||||
writeSTM :: s -> STM s ()
|
||||
writeSTM s = stmr (const ((),s))
|
||||
|
||||
done :: Monad m => m ()
|
||||
done = return ()
|
||||
|
||||
class Monad m => ErrorMonad m where
|
||||
raise :: String -> m a
|
||||
handle :: m a -> (String -> m a) -> m a
|
||||
handle_ :: m a -> m a -> m a
|
||||
handle_ a b = a `handle` (\_ -> b)
|
||||
|
||||
instance ErrorMonad Err where
|
||||
raise = Bad
|
||||
handle a@(Ok _) _ = a
|
||||
handle (Bad i) f = f i
|
||||
|
||||
instance ErrorMonad (STM s) where
|
||||
raise msg = STM (\s -> raise msg)
|
||||
handle (STM f) g = STM (\s -> (f s)
|
||||
`handle` (\e -> let STM g' = (g e) in
|
||||
g' s))
|
||||
-- if the first check fails try another one
|
||||
checkAgain :: ErrorMonad m => m a -> m a -> m a
|
||||
checkAgain c1 c2 = handle_ c1 c2
|
||||
|
||||
checks :: ErrorMonad m => [m a] -> m a
|
||||
checks [] = raise "no chance to pass"
|
||||
checks cs = foldr1 checkAgain cs
|
||||
|
||||
allChecks :: ErrorMonad m => [m a] -> m [a]
|
||||
allChecks ms = case ms of
|
||||
(m: ms) -> let rs = allChecks ms in handle_ (liftM2 (:) m rs) rs
|
||||
_ -> return []
|
||||
|
||||
Reference in New Issue
Block a user