[Haskell-cafe] Rank N Kinds

Wvv vitea3v at rambler.ru
Sat Aug 10 22:04:43 CEST 2013

Paradoxes there are at logic and math. At programing languages we have bugs or
features :))

Higher universe levels are needed first of all for more abstract programming.

P.S. By the way, we don't need have extra TupleList, we have already list!

t3 :: [ (Int :: **) -> (Bool -> Bool -> Bool :: **) -> (String :: **) ]
t3 = [42 :: Int, (&&), "This is true *** type" ]

> :k t3

> head t3
42 :: Int

> (head $ tail t3) True True
True :: Bool


  2 Aug 2013 at 5:34:26, Daniel Peebles [via Haskell]
  (ml-node+s1045720n5733708h87 at n5.nabble.com) wrote:

  The higher universe levels are mostly "used" to stave off logical paradoxes
  in languages where you care about that kind of stuff. In a fundamentally
  impredicative language like Haskell I don't see much point, but I'd be happy
  to find there is one :)

  On Thu, Aug 1, 2013 at 4:55 PM, Wvv <[hidden email]> wrote:

    The right one is `instance Functor TupleList where ...`

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