[Haskell-beginners] Function result being inversed

[Tobias Brandt]

f (<) 3 == (<) 4 3 == 4 < 3 == False

On 25 January 2011 21:00, Xavier Shay <xavier-list at rhnh.net> wrote:
> Hello,
> I am confused by the following code.
> I would expect results of True, False.
>
> $ ghci
> *Main> let f x = x 4
> *Main> f(<) 3
> False
> *Main> f(<) 5
> True
>
> This came about because I was trying to refactor a sort function I wrote:
>
>  mySort [] = []
>  mySort (h:t) =
>    (f (<= h)) ++ [h] ++ (f (> h))
>    where f x = mySort (filter x t)
>
> I came up with this, which appears to work, though the comparison operators
> are backwards.
>
>  mySort [] = []
>  mySort (h:t) =
>    f(>) ++ [h] ++ f(<=)
>    where f x = mySort (filter (x h) t)
>
> Cheers,
> Xavier
>
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