haskell - Meaning of a newtype statement -

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i have statement:

newtype state st = state (st -> (st, a))

hence type of state is:

state :: (st -> (st, a)) -> state st

i cannot understand meaning:

  • are st , a placeholder of 2 data-type? right?
  • does statement means state function take argument function?

yes , yes. st state type , a answer type.


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