Selection Monad

Ben Gamari ben at
Thu Feb 2 18:18:54 UTC 2017

Jakub Daniel <jakub.daniel at> writes:

> Hi Eric,
> Just to clarify, my question was not about endorsing another library but
> rather extending the ones currently maintained by the committee with
> definition of a notion closely related to what is already contained in the
> libraries. It just so happens that Edward Kmett implemented the notion in a
> standalone library. However to me it does not make much sense to include
> ContT but not SelT (currently under the name Search) in the core libraries,
> despite their connection. I understand if this does not change the answer
> though.
Admittedly the symmetry here is quite intriguing,

    data Sel  r x = Sel  {runSel  :: (x → r) → x}

    data Cont r x = Cont {runCont :: (x → r) → r}

In light of this I can see why one might say that including one yet not
the other is odd. That being said, I'm not on the CLC so this is merely
an idle observation.


- Ben

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