learning to love laziness

[Richard Nathan Linger]

On Wed, 24 Sep 2003, Norman Ramsey wrote:

> Consider the following Haskell function:
> 
> > asPair x = (fst x, snd x)
> 
> This function has type forall a b. (a, b) -> (a, b)
> and is almost equivalent to the identity function, except it
> can be used to make programs terminate that might otherwise fall
> into a black hole.
> 

What is an example program that asPair rescues from nontermination?

Nathan