[Haskell-cafe] Syntax extension - adding import support to let/where bindings

Richard Eisenberg eir at cis.upenn.edu
Fri Aug 7 15:16:43 UTC 2015

This all seems to be solidifying nicely. From my perspective, I didn't really like the original proposal, but am now in favor of where it has evolved -- with all imports declared at the top, and then adding `import ...` to the syntax of local declarations. I'm not sure where the trouble around instances comes from in this idea, though. Even if a module is imported qualified, all of its instances are available anywhere, and I don't see that changing here. As Edward said, this would just be a small change in the renamer.

Is it time to make a wiki page and post a feature request? I think so.


On Aug 7, 2015, at 4:26 AM, Oliver Charles <ollie at ocharles.org.uk> wrote:

> On Thu, Aug 6, 2015 at 6:19 AM Vlatko Basic <vlatko.basic at gmail.com> wrote:
> The old Turbo Pascal keyword "with" (used for records) popped up in my mind. 
> It's rather clear for namespace resolution  and would look something like this:
>   with Data.ByteString $ do
>      map f ...
>   with Prelude $ do
>      map f ...
> or more explicit
>   withImport Data.ByteString $ do
>      ....
> One problem with this is that it forces an ordering on statements. Sometimes you might want to push the imports to the side, by moving them to a where clause, rather than a let binding. I'm hoping that whatever we propose would allow you to do this. That's why I think the syntax construct needs to be something that appears at the time of doing bindings.
> ocharles 
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/haskell-cafe/attachments/20150807/243347d5/attachment.html>

More information about the Haskell-Cafe mailing list