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mapping - Haskell: how to map a tuple?

In Haskell, I can easily map a list:

map (x -> 2*x) [1,2]

gives me [2,4]. Is there any "mapTuple" function which would work like that?

mapTuple (x -> 2*x) (1,2)

with the result being (2,4).

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Here's a rather short point-free solution:

import Control.Monad (join)
import Control.Arrow ((***))

mapTuple = join (***)

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