Re: Best practices for Arrows?
Tom Ellis <tom-lists-haskell-cafe-2013 <at> jaguarpaw.co.uk>
2013-11-13 19:09:42 GMT
On Sat, Jun 22, 2013 at 10:24:23PM +0100, Ross Paterson wrote:
> On Sat, Jun 22, 2013 at 07:05:09PM +0100, Tom Ellis wrote:
> > On Sat, Jun 22, 2013 at 03:36:15PM +0200, Ertugrul Söylemez wrote:
> > > If the interface is not under your control, make yourself comfortable
> > > with the complete arrow syntax, most notably how it handles operators,
> > > combinators and the `(| banana bracket notation |)`. This is very
> > > valuable information.
> > Interesting. I hadn't noticed the `(| banana bracket notation |)` on the
> > GHC Arrows page before, but just saw it when I went back to check.
> The banana brackets can be handy when you have operations on your arrow
> type beyond the ones in Arrow and ArrowLoop. But beware that the types of
> the operations you can use with it will be changing in the next release
> of GHC. The change is the first one described on
Is there any example of using Arrow banana brackets? I downloaded all of
Hackage and grepped it, and the only usage was in the comments of
I have feeling these might be useful to me, but I can't quite understand how