treeseq (empty) → 1.0.0.20180213

raw patch · 5 files changed

+1045/−0 lines, 5 filesdep +basedep +containers

Dependencies added: base, containers

Files

• COPYING +674/−0
• Data/TreeSeq/Strict.hs +67/−0
• Data/TreeSeq/Strict/Zipper.hs +257/−0
• stack.yaml +3/−0
• treeseq.cabal +44/−0

@@ -0,0 +1,674 @@+                    GNU GENERAL PUBLIC LICENSE+                       Version 3, 29 June 2007++ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>+ Everyone is permitted to copy and distribute verbatim copies+ of this license document, but changing it is not allowed.++                            Preamble++  The GNU General Public License is a free, copyleft license for+software and other kinds of works.++  The licenses for most software and other practical works are designed+to take away your freedom to share and change the works.  By contrast,+the GNU General Public License is intended to guarantee your freedom to+share and change all versions of a program--to make sure it remains free+software for all its users.  We, the Free Software Foundation, use the+GNU General Public License for most of our software; it applies also to+any other work released this way by its authors.  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If not, see <http://www.gnu.org/licenses/>.++Also add information on how to contact you by electronic and paper mail.++  If the program does terminal interaction, make it output a short+notice like this when it starts in an interactive mode:++    <program>  Copyright (C) <year>  <name of author>+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.+    This is free software, and you are welcome to redistribute it+    under certain conditions; type `show c' for details.++The hypothetical commands `show w' and `show c' should show the appropriate+parts of the General Public License.  Of course, your program's commands+might be different; for a GUI interface, you would use an "about box".++  You should also get your employer (if you work as a programmer) or school,+if any, to sign a "copyright disclaimer" for the program, if necessary.+For more information on this, and how to apply and follow the GNU GPL, see+<http://www.gnu.org/licenses/>.++  The GNU General Public License does not permit incorporating your program+into proprietary programs.  If your program is a subroutine library, you+may consider it more useful to permit linking proprietary applications with+the library.  If this is what you want to do, use the GNU Lesser General+Public License instead of this License.  But first, please read+<http://www.gnu.org/philosophy/why-not-lgpl.html>.

@@ -0,0 +1,67 @@+module Data.TreeSeq.Strict where++import Control.Applicative (Applicative(..))+import Control.Monad (Monad(..))+import Data.Eq (Eq(..))+import Data.Foldable (Foldable(..))+import Data.Function (($), (.))+import Data.Functor (Functor(..), (<$>))+import Data.Monoid (Monoid(..))+import Data.Ord (Ord(..))+import Data.Semigroup (Semigroup(..))+import Data.Sequence (Seq, ViewL(..))+import Data.Traversable (Traversable(..))+import Text.Show (Show(..))+import qualified Data.List as List+import qualified Data.Sequence as Seq++-- * Type 'Tree'+data Tree a+ =   Tree { unTree   :: !a+          , subTrees :: !(Trees a)+          }+ deriving (Eq, Ord, Show)+instance Functor Tree where+	fmap f (Tree a ts) = Tree (f a) (fmap (fmap f) ts)+instance Applicative Tree where+	pure a = Tree a mempty+	Tree f tfs <*> ta@(Tree a tas) =+		Tree (f a) (fmap (f <$>) tas <> fmap (<*> ta) tfs)+instance Monad Tree where+	return = pure+	Tree a ts >>= f =+		Tree a' (ts' <> fmap (>>= f) ts)+		where Tree a' ts' = f a+instance Foldable Tree where+	foldMap f (Tree a ts) = f a `mappend` foldMap (foldMap f) ts+instance Traversable Tree where+	traverse f (Tree a ts) = Tree <$> f a <*> traverse (traverse f) ts+	sequenceA  (Tree a ts) = Tree <$>   a <*> traverse sequenceA ts++tree0 :: a -> Tree a+tree0 a = Tree a mempty++isTree0 :: Tree a -> Bool+isTree0 (Tree _ ts) = null ts++isTreeN :: Tree a -> Bool+isTreeN (Tree _ ts) = not (null ts)++-- * Type 'Trees'+type Trees a = Seq (Tree a)++prettyTree :: Show a => Tree a -> String+prettyTree = List.unlines . pretty++prettyTrees :: Show a => Trees a -> String+prettyTrees = foldr (\t acc -> prettyTree t <> "\n" <> acc) ""++pretty :: Show a => Tree a -> [String]+pretty (Tree a ts0) = show a : prettySubTrees ts0+	where+	shift first other = List.zipWith (<>) $ first : List.repeat other+	prettySubTrees s =+		case Seq.viewl s of+		 Seq.EmptyL -> []+		 t:<ts | Seq.null ts -> "|" : shift "`- " "   " (pretty t)+		       | otherwise   -> "|" : shift "+- " "|  " (pretty t) <> prettySubTrees ts

@@ -0,0 +1,257 @@+module Data.TreeSeq.Strict.Zipper where++import Control.Arrow (Kleisli(..))+import Control.Category (Category(..), (>>>))+import Control.Applicative (Applicative(..), Alternative(..))+import Data.Bool+import Data.Eq (Eq)+import Data.Function (($))+import Data.Functor ((<$>))+import Data.Int (Int)+import Data.List.NonEmpty (NonEmpty(..))+import Data.Maybe (Maybe(..), maybe, mapMaybe)+import Data.Monoid (Monoid(..))+import Data.Semigroup (Semigroup(..))+import Data.Sequence (ViewL(..), ViewR(..), (<|), (|>))+import Data.Typeable (Typeable)+import Prelude (undefined)+import Text.Show (Show(..))+import qualified Data.List as List+import qualified Data.List.NonEmpty as NonEmpty+import qualified Data.Sequence as Seq++import Data.TreeSeq.Strict (Trees, Tree(..))++-- * Type 'Zipper'+type Zipper a = NonEmpty (Cursor a)++-- | Return a 'Zipper' starting at the given 'Tree'.+zipper :: Tree a -> Zipper a+zipper t = Cursor mempty t mempty :| []++-- | Return a 'Zipper' starting at the left-most 'Tree' of the given 'Trees'.+zippers :: Trees a -> [Zipper a]+zippers ts =+	case Seq.viewl ts of+	 EmptyL -> empty+	 l :< ls -> pure $ Cursor mempty l ls :| []++-- | Return the 'Cursor' after zipping the given 'Zipper' upto its last parent.+root :: Zipper a -> Cursor a+root = NonEmpty.head . List.last . runAxis axis_ancestor_or_self++-- | Like 'root', but concatenate the 'Cursor' into a 'Trees'.+roots :: Zipper a -> Trees a+roots z = ps <> (s <| fs)+	where Cursor ps s fs = root z++-- | Return the keys within the 'Tree' nodes+-- leading to the current 'Cursor' of the given 'Zipper'.+zipath :: Zipper a -> [a]+zipath z =+	List.reverse $+	unTree . cursor_self+	 <$> NonEmpty.toList z++-- | Return the 'Tree's selected by the given 'Axis' from the given 'Zipper'.+select :: Axis a -> Zipper a -> [Tree a]+select axis z = cursor_self . NonEmpty.head <$> runAxis axis z++-- | Return the filtered values selected by the given 'Axis' from the given 'Zipper'.+filter :: Axis a -> (Zipper a -> Maybe b) -> Zipper a -> [b]+filter axis f z = f `mapMaybe` runAxis axis z++-- ** Type 'Cursor'+data Cursor a+ =   Cursor+ {   cursor_preceding_siblings :: Trees a+ ,   cursor_self               :: Tree  a+ ,   cursor_following_siblings :: Trees a+ } deriving (Eq, Show, Typeable)++-- | Return the current 'Cursor' of a 'Zipper'.+cursor :: Zipper a -> Cursor a+cursor = NonEmpty.head++-- | Set the current 'Cursor' of a 'Zipper'.+setCursor :: Zipper a -> Cursor a -> Zipper a+setCursor (_c :| cs) c = c :| cs++-- | Return the 'Tree' currently under the 'Cursor'.+current :: Zipper a -> Tree a+current (Cursor _ t _ :| _) = t++-- ** Type 'Axis'+type Axis a = AxisAlt [] a++runAxis :: Axis a -> Zipper a -> [Zipper a]+runAxis = runKleisli++-- ** Type 'AxisAlt'+-- | Like 'Axis', but generalized with 'Alternative'.+--+-- Useful to return a 'Maybe' instead of a list.+type AxisAlt f a = Kleisli f (Zipper a) (Zipper a)++runAxisAlt :: AxisAlt f a -> Zipper a -> f (Zipper a)+runAxisAlt = runKleisli++-- ** Axis @repeat@+-- | Collect all 'Zipper's along a given axis,+--   including the first 'Zipper'.+axis_repeat :: AxisAlt Maybe a -> Axis a+axis_repeat f = Kleisli $ \z -> z : maybe [] (runAxis $ axis_repeat f) (runAxisAlt f z)++-- | Collect all 'Zipper's along a given axis,+--   excluding the starting 'Zipper'.+axis_repeat_without_self :: AxisAlt Maybe a -> Axis a+axis_repeat_without_self f = Kleisli $ \z -> maybe [] (runAxis $ axis_repeat f) (runAxisAlt f z)++-- ** Axis @filter@+axis_filter :: Axis a -> (Zipper a -> Bool) -> Axis a+axis_filter axis f = Kleisli $ \z -> List.filter f (runAxis axis z)+infixl 5 `axis_filter`++axis_filter_current :: Axis a -> (Tree a -> Bool) -> Axis a+axis_filter_current axis f = Kleisli $ \z -> List.filter (f . current) (runAxis axis z)+infixl 5 `axis_filter_current`++-- ** Axis @first@+axis_first :: Axis a -> Axis a+axis_first axis = Kleisli $ List.take 1 . runAxis axis++-- ** Axis @last@+axis_last :: Axis a -> Axis a+axis_last axis = Kleisli $ List.take 1 . List.reverse . runAxis axis++-- ** Axis @at@+axis_at :: Alternative f => Axis a -> Int -> AxisAlt f a+axis_at axis i = Kleisli $ \z ->+	case List.drop i $ runAxis axis z of+	 []  -> empty+	 a:_ -> pure a+infixl 5 `axis_at`++-- ** Axis @self@+axis_self :: Applicative f => AxisAlt f a+axis_self = Kleisli pure++-- ** Axis @child@+axis_child :: Axis a+axis_child =+	axis_child_first >>>+	axis_repeat axis_following_sibling_nearest++axis_child_lookup_first :: Alternative f => (a -> Bool) -> AxisAlt f a+axis_child_lookup_first fa = Kleisli $ listHead . runAxis (axis_child_lookup fa)++axis_child_lookup :: (a -> Bool) -> Axis a+axis_child_lookup f = Kleisli $ \z@(Cursor _ps t _fs :| _) ->+	let ns = subTrees t in+	(<$> Seq.findIndicesL (f . unTree) ns) $ \i ->+		let (ps, ps') = Seq.splitAt i ns in+		case Seq.viewl ps' of+		 EmptyL -> undefined+		 l :< ls -> Cursor ps l ls :| NonEmpty.toList z++axis_child_first :: Alternative f => AxisAlt f a+axis_child_first = Kleisli $ \z@(Cursor _ps t _fs :| _) ->+	case Seq.viewl $ subTrees t of+	 EmptyL -> empty+	 l :< ls -> pure $ Cursor mempty l ls :| NonEmpty.toList z++axis_child_last :: Alternative f => AxisAlt f a+axis_child_last = Kleisli $ \z@(Cursor _ps t _fs :| _) ->+	case Seq.viewr $ subTrees t of+	 EmptyR -> empty+	 rs :> r -> pure $ Cursor rs r mempty :| NonEmpty.toList z++-- ** Axis @ancestor@+axis_ancestor :: Axis a+axis_ancestor = axis_repeat_without_self axis_parent++axis_ancestor_or_self :: Axis a+axis_ancestor_or_self = axis_repeat axis_parent++axis_root :: Alternative f => AxisAlt f a+axis_root = Kleisli $ pure . List.last . runAxis axis_ancestor_or_self++-- ** Axis @descendant@+axis_descendant_or_self :: Axis a+axis_descendant_or_self =+	Kleisli $ collect_child []+	where+	collect_child acc z =+		z : maybe acc+		 (collect_following_first acc)+		 (runAxisAlt axis_child_first z)+	collect_following_first acc z =+		collect_child+		 (maybe acc+			 (collect_following_first acc)+			 (runAxisAlt axis_following_sibling_nearest z)+		 ) z++axis_descendant_or_self_reverse :: Axis a+axis_descendant_or_self_reverse = Kleisli go+	where go z = z : List.concatMap go (List.reverse $ runAxis axis_child z)++axis_descendant :: Axis a+axis_descendant = Kleisli $ List.tail . runAxis axis_descendant_or_self++-- ** Axis @preceding@+axis_preceding_sibling :: Axis a+axis_preceding_sibling = axis_repeat_without_self axis_preceding_sibling_nearest++axis_preceding_sibling_nearest :: Alternative f => AxisAlt f a+axis_preceding_sibling_nearest = Kleisli $ \(Cursor ps t fs :| cs) ->+	case Seq.viewr ps of+	 EmptyR  -> empty+	 rs :> r -> pure $ Cursor rs r (t <| fs) :| cs++axis_preceding_sibling_farthest :: Alternative f => AxisAlt f a+axis_preceding_sibling_farthest = Kleisli $ \z@(Cursor ps t fs :| cs) ->+	case Seq.viewl (ps |> t) of+	 EmptyL  -> pure z+	 l :< ls -> pure $ Cursor mempty l (ls<>fs) :| cs++axis_preceding :: Axis a+axis_preceding =+	axis_ancestor_or_self >>>+	axis_preceding_sibling >>>+	axis_descendant_or_self_reverse++-- ** Axis @following@+axis_following_sibling :: Axis a+axis_following_sibling = axis_repeat_without_self axis_following_sibling_nearest++axis_following_sibling_nearest :: Alternative f => AxisAlt f a+axis_following_sibling_nearest = Kleisli $ \(Cursor ps t fs :| cs) ->+	case Seq.viewl fs of+	 EmptyL  -> empty+	 l :< ls -> pure $ Cursor (ps |> t) l ls :| cs++axis_following_sibling_farthest :: Alternative f => AxisAlt f a+axis_following_sibling_farthest = Kleisli $ \z@(Cursor ps t fs :| cs) ->+	case Seq.viewr (t <| fs) of+	 EmptyR  -> pure z+	 rs :> r -> pure $ Cursor (ps<>rs) r mempty :| cs++axis_following :: Axis a+axis_following =+	axis_ancestor_or_self >>>+	axis_following_sibling >>>+	axis_descendant_or_self++-- ** Axis @parent@+axis_parent :: Alternative f => AxisAlt f a+axis_parent = Kleisli $ \(Cursor ps t fs :| cs) ->+	case cs of+	 Cursor ps' (Tree a _) fs' : cs' ->+		pure $ Cursor ps' (Tree a $ (ps |> t) <> fs) fs' :| cs'+	 _ -> empty++-- * Utilities+listHead :: Alternative f => [a] -> f a+listHead []    = empty+listHead (a:_) = pure a

@@ -0,0 +1,3 @@+resolver: lts-10.5+packages:+- '.'

@@ -0,0 +1,44 @@+name: treeseq+-- PVP:  +-+------- breaking API changes+--       | | +----- non-breaking API additions+--       | | | +--- code changes with no API change+version: 1.0.0.20180213+category: Data Structures+synopsis: Library for a multi-way tree (rose tree), using Seq (finger tree) for forests+description: Like 'Data.Tree' of @containers@,+             but use 'Data.Sequence' instead of 'Data.List' for forests ('Trees').+extra-doc-files:+license: GPL-3+license-file: COPYING+stability: experimental+author:      Julien Moutinho <julm+treeseq@autogeree.net>+maintainer:  Julien Moutinho <julm+treeseq@autogeree.net>+bug-reports: Julien Moutinho <julm+treeseq@autogeree.net>+-- homepage:++build-type: Simple+cabal-version: >= 1.18+tested-with: GHC==8.2.2+extra-source-files:+  stack.yaml+extra-tmp-files:++Source-Repository head+ location: git://git.autogeree.net/treeseq+ type:     git++Library+  exposed-modules:+    Data.TreeSeq.Strict+    Data.TreeSeq.Strict.Zipper+  default-language: Haskell2010+  default-extensions:+  ghc-options:+    -Wall+    -Wincomplete-uni-patterns+    -Wincomplete-record-updates+    -fno-warn-tabs+    -- -fhide-source-paths+  build-depends:+      base         >= 4.10 && < 5+    , containers   >= 0.5