[Haskell-cafe] Newtype derivation understanding problem

Konstantine Rybnikov k-bx at k-bx.com
Thu Jul 31 10:55:32 UTC 2014

Excuse me if the question is silly.

Thought this MonadCatchIO will be removed in next version of snap, current
version has it and I can't understand this derivation: [0]

L.Lensed seems like just a newtype wrapper around a function [1], and there
is no instance of MonadCatchIO for a function.

How is it derived?

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20140731/84429a19/attachment.html>

More information about the Haskell-Cafe mailing list