And to finish the example, fully parenthesized: Prelude> let x = 4 Prelude> let y = [1,2,3,4] Prelude> let z = 3 Prelude> map ((flip (f x)) z) y [7,11,15,19] I.e., apply f to x, flip the arguments, apply z, and map the result across y. On 09/13/2010 09:01 AM, Alex Rozenshteyn wrote:

To actually give the example:

...

-- assuming that x and z are defined, and ys is the list map (\y -> f x y z) ys

On Mon, Sep 13, 2010 at 9:16 AM, Magnus Therning mailto:magnus@therning.org> wrote:

On Mon, Sep 13, 2010 at 14:03, Lorenzo Isella mailto:lorenzo.isella@gmail.com> wrote: > Dear All, > Suppose you have the function > > f x y z = x*y +z > > and that you want to iterate it on a list > z=[1,2,3,4], with > x=4 and y=3 > > then you would do the following > > map (f x y) z. > > Now consider the case in which the list is given by y e.g. > > y=[1,2,3,4], with > x=4 and z=3. > > How can you iterate f on y (i.e. its second argument) while keeping x and y > fixed?

Using a lambda expression (anonymous function) or through clever use of flip.

/M

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