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Changed directory: /home/hugo/Academic/Teaching/2022.2/TCPF/Aulas/
λ> :i Talvez

<interactive>:1:1-6: error: Not in scope: ‘Talvez’
λ> :t Talvez

<interactive>:1:1-6: error: Data constructor not in scope: Talvez
λ> :t Talvez

<interactive>:1:1-6: error: Data constructor not in scope: Talvez
λ> :t Talvez

<interactive>:1:1-6: error: Data constructor not in scope: Talvez
λ> :k Talvez
Talvez :: * -> *
λ> :t Talvez

<interactive>:1:1-6: error: Data constructor not in scope: Talvez
λ> :t DeFato
DeFato :: a -> Talvez a
λ> :t Applicative

<interactive>:1:1-11: error:
    Data constructor not in scope: Applicative
λ> :i Applicative
type Applicative :: (* -> *) -> Constraint
class Functor f => Applicative f where
  pure :: a -> f a
  (<*>) :: f (a -> b) -> f a -> f b
  GHC.Base.liftA2 :: (a -> b -> c) -> f a -> f b -> f c
  (*>) :: f a -> f b -> f b
  (<*) :: f a -> f b -> f a
  {-# MINIMAL pure, ((<*>) | liftA2) #-}
  	-- Defined in ‘GHC.Base’
instance Applicative Talvez -- Defined at Aula27.hs:29:10
instance Applicative (Either e) -- Defined in ‘Data.Either’
instance Applicative [] -- Defined in ‘GHC.Base’
instance Applicative Maybe -- Defined in ‘GHC.Base’
instance Applicative IO -- Defined in ‘GHC.Base’
instance Applicative ((->) r) -- Defined in ‘GHC.Base’
instance (Monoid a, Monoid b, Monoid c) =>
         Applicative ((,,,) a b c)
  -- Defined in ‘GHC.Base’
instance (Monoid a, Monoid b) => Applicative ((,,) a b)
  -- Defined in ‘GHC.Base’
instance Monoid a => Applicative ((,) a) -- Defined in ‘GHC.Base’
λ> DeFato (+4) <*> DeFato 10
DeFato 14
λ> DeFato (+4) <*> Nada
Nada
λ> :t Either

<interactive>:1:1-6: error:
    • Data constructor not in scope: Either
    • Perhaps you meant variable ‘either’ (imported from Prelude)
λ> :i Either
type Either :: * -> * -> *
data Either a b = Left a | Right b
  	-- Defined in ‘Data.Either’
instance Applicative (Either e) -- Defined in ‘Data.Either’
instance (Eq a, Eq b) => Eq (Either a b)
  -- Defined in ‘Data.Either’
instance Functor (Either a) -- Defined in ‘Data.Either’
instance Monad (Either e) -- Defined in ‘Data.Either’
instance (Ord a, Ord b) => Ord (Either a b)
  -- Defined in ‘Data.Either’
instance Semigroup (Either a b) -- Defined in ‘Data.Either’
instance (Show a, Show b) => Show (Either a b)
  -- Defined in ‘Data.Either’
instance (Read a, Read b) => Read (Either a b)
  -- Defined in ‘Data.Either’
instance Foldable (Either a) -- Defined in ‘Data.Foldable’
instance Traversable (Either a) -- Defined in ‘Data.Traversable’
λ> Vaca {"Malhada", 300}

<interactive>:133:7: error: parse error on input ‘"’
λ> Vaca {nome="Malhada", peso=300}
Vaca {nome = "Malhada", peso = 300}
λ> Vaca "Malhada" 300 
Vaca {nome = "Malhada", peso = 300}
λ> :t Vaca
Vaca :: String -> Integer -> Vaca
λ> constroiVaca "Malhada" 300
DeFato (Vaca {nome = "Malhada", peso = 300})
λ> constroiVaca "Malhada" -300

<interactive>:186:1-27: error:
    • No instance for (Num (Integer -> Talvez Vaca))
        arising from a use of ‘-’
        (maybe you haven't applied a function to enough arguments?)
    • In the expression: constroiVaca "Malhada" - 300
      In an equation for ‘it’: it = constroiVaca "Malhada" - 300
λ> constroiVaca "Malhada" (-300)
Nada
λ> constroiVaca "" 300
Nada
λ> :t Vaca
Vaca :: String -> Integer -> Vaca
λ>  pure Vaca
λ> :t pure Vaca
pure Vaca :: Applicative f => f (String -> Integer -> Vaca)
λ> 
λ> constroiVaca "Malhada" 300
DeFato (Vaca {nome = "Malhada", peso = 300})
λ> constroiVaca "Malhada" 0
Nada
λ> :t Vaca
Vaca :: String -> Integer -> Vaca
λ> :t Vaca "Malhada"
Vaca "Malhada" :: Integer -> Vaca
λ> :t DeFato (Vaca "Malhada")
DeFato (Vaca "Malhada") :: Talvez (Integer -> Vaca)
λ> import Control.Applicative
λ> :t liftA3
liftA3
  :: Applicative f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d
λ> :t liftA4

<interactive>:1:1-6: error:
    • Variable not in scope: liftA4
    • Perhaps you meant one of these:
        ‘liftA2’ (imported from Control.Applicative),
        ‘liftA’ (imported from Control.Applicative),
        ‘liftA3’ (imported from Control.Applicative)
λ> :t liftA
liftA :: Applicative f => (a -> b) -> f a -> f b
λ> :t liftA0

<interactive>:1:1-6: error:
    • Variable not in scope: liftA0
    • Perhaps you meant one of these:
        ‘liftA2’ (imported from Control.Applicative),
        ‘liftA’ (imported from Control.Applicative),
        ‘liftA3’ (imported from Control.Applicative)
λ> :t Erro
Erro :: a -> UmOuOutro a b
λ> :t pure (.)
pure (.) :: Applicative f => f ((b -> c) -> (a -> b) -> a -> c)
λ>