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Changed directory: /home/hugo/Academic/Teaching/2023.2/TCPF/Aulas/
λ> somarFold (Suc $ Suc 2)

<interactive>:9:22: error:
    * No instance for (Num Natural) arising from the literal `2'
      There are instances for similar types:
        instance Num GHC.Num.Natural.Natural -- Defined in `GHC.Num'
    * In the first argument of `Suc', namely `2'
      In the second argument of `($)', namely `Suc 2'
      In the first argument of `somarFold', namely `(Suc $ Suc 2)'
λ> somarFold (Suc $ Suc Zero) (Suc $ Suc $ Suc Zero)
Suc (Suc (Suc (Suc (Suc Zero))))
λ> produtoFold (Suc $ Suc Zero) (Suc $ Suc $ Suc Zero)
Suc (Suc (Suc (Suc (Suc (Suc Zero)))))
λ> potenciaFold (Suc $ Suc Zero) (Suc $ Suc $ Suc Zero)
Suc (Suc (Suc (Suc (Suc (Suc (Suc (Suc Zero)))))))
λ> potenciaFold (Suc $ Suc $ Suc Zero) (Suc $ Suc Zero)
Suc (Suc (Suc (Suc (Suc (Suc (Suc (Suc (Suc Zero))))))))
λ> t
No 65 Folha (No 3 (No 0 Folha Folha) Folha)
λ> foldArv (\ x y z -> x+y+z) 0 t
68
λ> foldArv (\ x y z -> x*y*z) 1 t
0
λ> :i Foldable
type Foldable :: (* -> *) -> Constraint
class Foldable t where
  Data.Foldable.fold :: Monoid m => t m -> m
  foldMap :: Monoid m => (a -> m) -> t a -> m
  Data.Foldable.foldMap' :: Monoid m => (a -> m) -> t a -> m
  foldr :: (a -> b -> b) -> b -> t a -> b
  Data.Foldable.foldr' :: (a -> b -> b) -> b -> t a -> b
  foldl :: (b -> a -> b) -> b -> t a -> b
  Data.Foldable.foldl' :: (b -> a -> b) -> b -> t a -> b
  foldr1 :: (a -> a -> a) -> t a -> a
  foldl1 :: (a -> a -> a) -> t a -> a
  Data.Foldable.toList :: t a -> [a]
  null :: t a -> Bool
  length :: t a -> Int
  elem :: Eq a => a -> t a -> Bool
  maximum :: Ord a => t a -> a
  minimum :: Ord a => t a -> a
  sum :: Num a => t a -> a
  product :: Num a => t a -> a
  {-# MINIMAL foldMap | foldr #-}
  	-- Defined in `Data.Foldable'
instance Foldable [] -- Defined in `Data.Foldable'
instance Foldable Solo -- Defined in `Data.Foldable'
instance Foldable Maybe -- Defined in `Data.Foldable'
instance Foldable (Either a) -- Defined in `Data.Foldable'
instance Foldable ((,) a) -- Defined in `Data.Foldable'
λ> foldr (+) 0 t
68
λ> :t toList

<interactive>:1:1-6: error: Variable not in scope: toList
λ> :t toList

<interactive>:1:1-6: error: Variable not in scope: toList
λ> arvParaList t
[65,3,0]
λ> t
No 65 Folha (No 3 (No 0 Folha Folha) Folha)
λ> :t toList
toList :: Foldable t => t a -> [a]
λ> toList t
[65,3,0]
λ> v
No 10 (No 5 Folha (No 6 Folha Folha)) (No 20 (No 15 Folha Folha) (No 100 Folha Folha))
λ> toList v
[10,20,100,15,5,6]
λ> arvParaList v
[10,5,6,20,15,100]
λ> toList v
[10,5,6,20,15,100]
λ> :t toList
toList :: Foldable t => t a -> [a]
λ> arvParaListFold v
[10,5,6,20,15,100]
λ> toList v
[10,5,6,20,15,100]
λ> arvParaList v
[10,5,6,20,15,100]
λ> n = 3
λ> :t n
n :: Num a => a
λ> n
3
λ> :t n
n :: Integer
λ>