[Haskell-cafe] Odd behavior with Num instance for lists (was: f^n for functional iteration)

[Dan Burton]

When using this hack, I prefer `fromInteger x = repeat (fromInteger x)`.
That way, you get

    > 2 * [1,2,3]
    [2,4,6]

It's cute for playing around, but the Num instance for lists is somewhat
discouraged in "real" code.


-- Dan Burton


On Fri, Dec 13, 2013 at 10:15 AM, Dario Bertini <berdario at gmail.com> wrote:

> I guess you meant
>
> (*) = zipWith (*)
> ?
>
> Dumb question: would it be fine to use such an instance in real world
> application code (in contrast with library code... I guess it would be
> frowned upon there?)
>
> are there any "dangers"... weird interactions?
>
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