Multi-Reactor Tutorial

I am writing a compiler in Haskell and need some tools for working with abstract syntax trees (for example, annotating with their original positions and other things). I was listed in the package multirec.

I found some information about the package, but it is too dense to read and understand, since the ideas are presented from a theoretical point of view.

So I'm looking for something easier, like tutorials or simple applications that illustrate the use of the package.

Any help?