Re: Generalizing some type signatures involving Int

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@outlook.com> wrote:

:+1: from me.

------------------------------ *From:* Libraries on behalf of Vanessa McHale *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