Re: Proposal: Determining whether a Bits instance is FiniteBits

Carter Schonwald <[email protected]>
Newsgroups gmane.comp.lang.haskell.libraries
Message-ID <CAHYVw0z4WzWP-PJSkx-UxwcMtO2fuLZw_pz4X6CZdL6GLwNdow@mail.gmail.com>
What would the final / eventual instance be defined as?

Or do you mean that would be a default stub so code doesn’t crash
immediately on upgrade if it doesn’t have a definition?

On Tue, May 18, 2021 at 12:30 PM Zemyla <[email protected]> wrote:

> Every Bits instance has to know that whether it's a FiniteBits
> instance as well, due to bitSizeMaybe. Therefore, it should also be
> able to tell a program that it is in fact a FiniteBits instance. There
> should be a function added to Data.Bits.Bits:
>
> withFiniteBits :: Bits a => a -> (FiniteBits a => r) -> r -> r
>
> The default should be withFiniteBits _ _ x = x, at least for the next
> several versions. bitSizeMaybe can be defined as
>
> bitSizeMaybe x = withFiniteBits x (Just (finiteBitSize x)) Nothing
>
> once everyone is on board with properly defining the value.
> _______________________________________________
> Libraries mailing list
> [email protected]
> http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries
>

_______________________________________________
Libraries mailing list
[email protected]
http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.