Determinig position of a element in a list

[Erik Max Francis]

Przemo Drochomirecki wrote:

> i'm wondering if there is any tricky way for doing following thing:
>     A - list of distinct integers  (e.x. A = [1,3,7,11,14,15])
>     very fast function determinig position of number x in list A
>     or -1 if x doesnt belong to A
> Operator IN returns only false/true values
> i can implement function index (e.x. index(5,A) = -1, index(7,A) = 2),
> but
> maybe there's is simpler(builtin?) solution

Yep, the -- wait for it -- .index method on the list object:

>>> A = [1, 3, 7, 11, 14, 15]
>>> A.index(7)
2

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   Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
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