[Haskell-cafe] Mystery operator?
jochem at functor.nl
Mon Nov 30 12:49:54 EST 2009
michael rice wrote:
> From: http://www.haskell.org/haskellwiki/Blow_your_mind#Polynomials
> -- splitting in two (alternating)
> -- "1234567" -> ("1357", "246")
> -- the lazy match with ~ is necessary for efficiency, especially enabling processing of infinite lists
> foldr (\a ~(x,y) -> (a:y,x)) (,)
> This works but can't find (~) operator anywhere. Please explain or site a reference.
This is called a "lazy pattern".
Jochem Berndsen | jochem at functor.nl | jochem@牛在田里.com
More information about the Haskell-Cafe