Generalizing some type signatures involving Int

[Eric Mertens]

Int is the right type to be able to do efficient internal operations when
implementing length and replicate. It's unlikely that someone would want to
run these operations on another type internally than Int. Some times people
propose types like these where they imagine just a built-in use of
fromIntegral on either the initial argument or the result, but that really
quite unnecessary. Could you elaborate on what cases you had in mind?

While genericLength exists, I have yet to see a good use of it.

Best regards,
Eric Mertens
glguy

On Tue, Nov 13, 2018 at 5:34 PM Alexandre Rodrigues <
alexandreR_B at outlook.com> wrote:

> :+1: from me.
>
>
> ------------------------------
> *From:* Libraries <libraries-bounces at haskell.org> on behalf of Vanessa
> McHale <vanessa.mchale at iohk.io>
> *Sent:* Wednesday, November 14, 2018 1:18:58 AM
> *To:* Haskell Libraries
> *Subject:* Generalizing some type signatures involving Int
>
> Would it be possible to generalize replicate and length to have type
> signatures
>
> replicate :: Integral a => a -> b -> [b]
>
> and
>
> length :: (Integral a, Foldable t) => t b -> a
>
> ?
>
> There have been a few instances where such a thing would have been
> useful to me.
>
> Cheers
>
>
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-- 
Eric Mertens
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