[Agda] examples for the Effect.Monad... modules in agda-stdlib/master?

[Peter Thiemann]

Dear list, 

Is there an accessible example for the material in the Effect.Monad module hierarchy in the main branch of the agda-stdlib repository (it's *not* in the current release 1.7.2, but appears to be in preparation for 2.0)?

Specifically, I'm interested in a simple stack of transformers
StateT X (ReaderT Y IO)
preferably set up so that the monads are available as instance arguments.

-Peter