well,
> selFn = map (\x -> (! x)) sel -- This is not necessarily the most elegant way to word it
would return a list of functions, which, when applied to a list, return an element from it based on the index
> results = map ($ ml) selFn
would solve your problem

alternatively (and more cleanly),
> results = map (ml !) sel

On Fri, Sep 10, 2010 at 10:55 AM, Lorenzo Isella <lorenzo.isella@gmail.com> wrote:
Dear All,
I know this must be a one-liner, but it am banging my head against the wall.
I am trying my hands at list manipulation in Haskell and a lot of useful function are making my life easier but I cannot achieve something really simple.
Let us say you have the lists ml and sel

ml=[23,44,55,8,98]
and
sel=[1,2] .

Now, I would like simply to get a new list whose entries are the elements of ml in position sel. In my case things might be a little more complicated because all the elements are Integer and not Int (I noticed that sometimes this means I have to resort to generic functions).
Cheers

Lorenzo
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          Alex R