Proposal: Adding on

Nils Anders Danielsson nad at
Fri Nov 3 07:23:59 EST 2006

On Thu, 02 Nov 2006, Duncan Coutts <duncan.coutts at> wrote:

> I wonder about how this relates to 'comparing' which we already have in
> Data.Ord. Does adding 'on' mean we should remove 'comparing' ?
> I would suggest we keep both and add 'equating' to Data.Eq too, for
> symmetry with 'comparing'.

I think it's just as easy to understand (compare `on` f) as (comparing
f), so having both just adds extra complexity. Hence I place comparing
_under_ the Fairbairn threshold.

My patch adds documentation to Data.List pointing to on, by the way.


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