[Haskell-cafe] List comparisons and permutation group code

[Henk-Jan van Tuyl]

How about this:
   import List
   isIdentity (PL xs) =  xs `isPrefixOf` [1..]
?

Best regards,
Henk-Jan van Tuyl


On Fri, 20 Oct 2006 01:01:33 +0200, Tomasz Zielonka  
<tomasz.zielonka at gmail.com> wrote:

> 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
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-- 
Met vriendelijke groet,
Henk-Jan van Tuyl


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