For example, in Haskell, a function that returns a particular Church integer might be

church 0 = \\ f x -> x church n = c where c f x = c' f (f x) where c' = church (n - 1)The transformation from a Church integer to an integer might be

unchurch n = n (+1) 0Thus the (+1) function would be applied to an initial value of 0

See lambda calculus for another expression of the same idea.

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