[Haskell-cafe] what does the '~' mean ?

instance (BinaryDefer a, BinaryDefer b) => BinaryDefer (a,b) where put (a,b) = put2 a b get = get2 (,) size x = let ~(a,b) = x in size a + size b putFixed (a,b) = putFixed2 a b getFixed = getFixed2 (,) in `size` function, what does the `~` mean ? Sincerely! ----- fac n = let { f = foldr (*) 1 [1..n] } in f -- View this message in context: http://old.nabble.com/what-does-the-%27%7E%27-mean---tp28263383p28263383.htm... Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.