[Haskell-beginners] MonadThrow, MonadReader and shake

Francesco Ariis fa-ml at ariis.it
Fri Dec 14 12:00:02 UTC 2018

On Fri, Dec 14, 2018 at 11:29:20AM +0000, PICCA Frederic-Emmanuel wrote:
> src/XdsMe.hs:214:31-52: error:
>     • Could not deduce (Control.Monad.Reader.Class.MonadReader
>                           Beamline IO)
>         arising from a use of ‘toRuchePath’
>       from the context: t ~ 'Collect

Are you by chance using existential quantification or gadts?

I might need a self contained example to load on ghci.

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