Help needed: Restrictions of proc-notation with RebindableSyntax

Boespflug, Mathieu m at
Wed Dec 21 16:52:34 UTC 2016

And Opaleye (a successor to haskellDB, for safe interaction with SQL
databases) also uses arrow notation last I checked. As I recall do-notation
is too powerful, whereas proc-notation provides exactly the right
expressive power (no illegal SQL queries can be expressed). But that's not
to say Tom (author of Opaleye) couldn't be content with a profunctor-based
desugaring rather than an Arrow-based one?

Mathieu Boespflug
Founder at

On 21 December 2016 at 16:31, Brandon Allbery <allbery.b at> wrote:

> On Wed, Dec 21, 2016 at 12:15 AM, Edward Kmett <ekmett at> wrote:
>> Given that little new code seems to be being written with Arrows in mind,
>> while some older code makes heavy use of it (hxt, etc.), refactoring the
>> arrow hierarchy is kind of a hard sell. It is by no means impossible, just
>> something that would require a fair bit of community wrangling and a lot of
>> work showing clear advantages to a new status quo at a time when its very
>> hard to get anybody to care about arrow notation at all.
> The arrowized-FRP folks seem to care a fair bit.
> --
> brandon s allbery kf8nh                               sine nomine
> associates
> allbery.b at
> ballbery at
> unix, openafs, kerberos, infrastructure, xmonad
> _______________________________________________
> ghc-devs mailing list
> ghc-devs at
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the ghc-devs mailing list