Writing a counter function

[Jon Fairbairn]

Shlomi Fish wrote:
> No. But I want to generate an irregular series, which I determine the
> intervals between two consecutive numbers myself. E.g:
> =

> let (num1, next1) =3D (counter 5)
>     (num2, next2) =3D (next1 100)
>     (num3, next3) =3D (next2 50) in
>     [num1,num2,num3]
> =

> Will have the numbers [5, 105, 155].

What do you mean by "determine"?

You can write =


sequence =3D iterate step_counter 0

if the interval between successive numbers is determined by
the current number, or

sequence =3D map f [1..]

if it's determined by the index in the sequence.

or =


sequence =3D  map snd $ iterate step_counter (0,-7)
step_counter (a,b) =3D (a+1, f a b) =


if it depends on both.


  J=F3n
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J=F3n Fairbairn                                 Jon.Fairbairn@cl.cam.ac.u=
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