If we're going to add this we should add the symmetric operation for
jam :: Either a a -> a
to Data.Either. (Name taken from Conal's compiling to categories code.)
My own code has called these diag and codiag respectively. I happily yield
to a nicer convention.
I have no real preference for whether we do the simple version in
Data.Tuple (which has a lot of precedent, as Data.Tuple tends to have lots
of little simple combinators that could be done more generally as arrows)
or moving it into Control.Arrow.
-Edward
On Sun, Oct 28, 2018 at 12:07 PM Ivan Perez
According to GHCi,
λ:> import Control.Arrow λ:> :t (id &&& id) (id &&& id) :: b -> (b, b)
That is, this implementation has type a -> (a, a) as well. Yes, yes, that's what I meant by "it works for functions as well (since
On 28/10/18 09:48, Vanessa McHale wrote: they are arrows)"
Ivan _______________________________________________ Libraries mailing list Libraries@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries