Help needed: Restrictions of proc-notation with RebindableSyntax

Tom Ellis tom-lists-haskell-cafe-2013 at
Wed Dec 21 17:18:51 UTC 2016

On Wed, Dec 21, 2016 at 05:52:34PM +0100, Boespflug, Mathieu wrote:
> 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?

I don't see any particular reason to oppose a profunctor-based desugaring. 
The structure of the computation would be the same, just encoded using
different classes.


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