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-- What is the type of (,)? When you use it in ghci, what does it do? What about
-- (,,)?
-- (,) is a 2-tuple data constructor
ghci> :t (,)
(,) :: a -> b -> (a, b)
ghci> (,) 1 2
(1,2)
ghci> t = (,) 1
ghci> :t t
t :: Num a => b -> (a, b)
ghci> t 2
(1,2)
-- (,,) is a 3-tuple data constructor
ghci> :t (,,)
(,,) :: a -> b -> c -> (a, b, c)
ghci> (,,) 1 2 3
(1,2,3)
ghci> t = (,,) 1
ghci> :t t
t :: Num a => b -> c -> (a, b, c)
ghci> u = t 2
ghci> :t u
u :: (Num a, Num b) => c -> (a, b, c)
ghci> u 3
(1,2,3)
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