[Haskell-cafe] Re: Gluing pipes

Matt Hellige matt at immute.net
Fri Dec 5 17:40:26 EST 2008

On Fri, Dec 5, 2008 at 11:35 AM, Stefan Monnier
<monnier at iro.umontreal.ca> wrote:
>>   \ x y -> f (g x) (h y)
> [...]
>>   f $. g ~> h ~> id
> I keep help wonder: other than a "5 chars", what is it we have gained?

Certainly in such a simple case, there's no benefit. In more complex
cases, especially where we're focused on just writing the combinator
itself (i.e., in cases where we won't use ($.)), I think it might make
sense (there is an example in the comments of Conal's recent post at

But anyway I do mean "might"... I happily admit the possibility that
this may be nothing more than a curiosity. I'm happy to have found a
solution to my little puzzle, but I'm not sure how often I'll actually
use it. Time will tell, I suppose.


More information about the Haskell-Cafe mailing list