Proposal: Add &&& and *** to Data.Tuple

Henrik Nilsson nhn at Cs.Nott.AC.UK
Fri Oct 19 06:09:12 EDT 2007

Hi all,

Sorry for my silence. Just too much to do to keep up.

So, with the risk of stating what has already been covered,
my concerns are that like Jon I find the reuse of names
unfortunate, especially if it is done in what appears to
be a very central module. Moreover, as functions are perfectly
legitimate arrow instances, I don't really see the point of it all,
and I remain unconvinced by the argument that importing
Control.Arrow somehow is complicated and scary.

It may well be, of course, that the current class hierarchy
isn't factored the right way, i.e. that operations like &&& and
*** should live some place else entirely. (This wouldn't be
the first instance of such problems.) That's a somewhat orthogonal
discussion, though. But defining &&& and *** in more places
certainly isn't going to help.

Again, my apologies if my answer is uninformed and/or missing
key points of the discussion.



Henrik Nilsson
School of Computer Science and Information Technology
The University of Nottingham
nhn at

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