Re: [Haskell-cafe] List comparisons and permutation group code

On Thu, Oct 19, 2006 at 04:03:38PM +0200, Mikael Johansson wrote:

isIdentity (PL xs) = all (\(i,j) -> i==j) (zip [1..] xs)

isIdentity (PL xs) = xs == [1..(length xs)]

How about a compromise? isIdentity (PL xs) = xs == zipWith const [1..] xs Best regards Tomasz