λ> :t Nil
Nil :: List a
λ> :t Cons
Cons :: a -> List a -> List a
λ> :k List
List :: * -> *
λ> :t []
[] :: [a]
λ> :t (:)
(:) :: a -> [a] -> [a]
λ> :k []
[] :: * -> *
λ> foldrBinTree (+) 0 t
*** Exception: /home/trifon/fmisync/Courses/2021_22/FP_2021_22/sandbox/lectures/haskell/Data.hs:168:1-81: Non-exhaustive patterns in function foldrBinTree

λ> foldrBinTree (+) 0 t
9
λ> tree
Tree {rootTree = 1, subtrees = SubTree {firstTree = Tree {rootTree = 2, subtrees = None}, restTrees = SubTree {firstTree = Tree {rootTree = 3, subtrees = SubTree {firstTree = Tree {rootTree = 4, subtrees = None}, restTrees = None}}, restTrees = SubTree {firstTree = Tree {rootTree = 5, subtrees = None}, restTrees = None}}}}
λ> :t map
map :: (a -> b) -> [a] -> [b]
λ> level 0 tree
[1]
λ> level 1 tree
[2,3,5]
λ> level 2 tree
[4]
λ> level 10 tree
[]
λ> sexpr
SList {list = [SInt 2,SChar 'a',SList {list = [SBool True,SDouble 1.2,SList {list = []}]}]}
λ> countAtoms sexpr
4
λ> countAtoms sexpr
4
λ> :t list
list :: SExpr -> [SExpr]
λ> flatten sexpr
SList {list = [SInt 2,SChar 'a',SBool True,SDouble 1.2]}
λ> flatten sexpr
SList {list = [SList {list = [SInt 2]},SList {list = [SChar 'a']},SList {list = [SList {list = [SBool True]},SList {list = [SDouble 1.2]},SList {list = []}]}]}
λ> sexpr
SList {list = [SInt 2,SChar 'a',SList {list = [SBool True,SDouble 1.2,SList {list = []}]}]}
λ> :t concatMap
concatMap :: Foldable t => (a -> [b]) -> t a -> [b]
λ> flatten sexpr
SList {list = [SInt 2,SChar 'a',SBool True,SDouble 1.2]}