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@Pzixel/

DarkturquoiseAliceblueMicrobsd

Haskell

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  • main.hs
main.hs
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import Data.Tree
import Data.Maybe

data Comment = Comment {
      title :: String
    , id  :: Int
    } deriving (Show)

getCommentById :: Int -> Maybe Comment
getCommentById i = Just $ Comment (show i) i

main :: IO ()
main = do
    let tree = Node 1 [Node 2 [], Node 3 [Node 4 [], Node 5 []]]
    putStrLn . drawTree . fmap show $ tree
    let commentsTree = mapM getCommentById tree
    putStrLn . drawTree . fmap show $ fromJust commentsTree
GHCi, version 8.6.5