Files
loop/src/Dodge/Tree/Compose.hs
T

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2.1 KiB
Haskell

{-| Combining and composing trees of trees. -}
module Dodge.Tree.Compose
( expandTree
, singleUseAll
, singleUseNone
, passUntilUseAll
, chainUses
, useAllAtEnd
, changeToPassDown
, overwriteLabel
) where
import Dodge.Tree.Compose.Data
import Dodge.Tree.Polymorphic
import Dodge.Base
import Data.Tree
expandTree :: CompTree a -> Tree a
expandTree (Node root extChildren) = case root of
Node (UseAll x) _ -> Node x (map expandTree extChildren)
Node (UseSome is x) _ -> Node x (map (expandTree . \i -> extChildren !! i) is)
Node (UseNone _) _ -> fmap _unCompose root
Node (UseLabel _ _) _ -> fmap _unCompose root
Node (PassDown x) xs -> Node x $ map (expandTree . (`Node` extChildren)) xs
Node (SplitDown x) xs -> Node x $ map expandTree $ zipWith Node xs
$ map (:[]) extChildren ++ repeat []
overwriteLabel :: Int -> (a -> ComposingNode a) -> SubCompTree a -> [SubCompTree a] -> SubCompTree a
overwriteLabel i f t ts = errorHead ("tried to overwriteLabel " ++ show i)
$ updateSingleNode islabel update t
where
islabel (UseLabel j _) | i == j = True
islabel _ = False
update (Node cr _) = Node (f $ _unCompose cr) ts
passUntilUseAll :: SubCompTree a -> [SubCompTree a] -> SubCompTree a
passUntilUseAll (Node (UseAll x) _) ts' = Node (PassDown x) ts'
passUntilUseAll (Node cn ts) ts' = Node (PassDown (_unCompose cn)) $ map (`passUntilUseAll` ts') ts
chainUses :: [SubCompTree a] -> SubCompTree a
chainUses (t:s:ts) = chainUses (passUntilUseAll t [s]:ts)
chainUses [t] = t
chainUses [] = error "tried to concatenate an empty list of SubCompTrees"
singleUseAll :: a -> Tree (ComposingNode a)
singleUseAll x = Node (UseAll x) []
useAllAtEnd :: Tree a -> SubCompTree a
useAllAtEnd tree = case tree of
Node x (t:ts) -> Node (PassDown x) (useAllAtEnd t : map (fmap UseNone) ts)
Node x [] -> Node (UseAll x) []
singleUseNone :: a -> SubCompTree a
singleUseNone x = Node (UseNone x) []
changeToPassDown :: ComposingNode a -> ComposingNode a
changeToPassDown x = PassDown (_unCompose x)