There is another book that is usually mentioned when comparing these two. Concepts, Techniques and Models of Computer Programming. I don't know how they all compare to each other, I just mention it for completeness sake.
an updated version that uses a current language would be nice, but the book isnt even open source (i.e. under the Creative Commons license)
Would it be easy to follow the book using Mercury language?
Years ago, the author taught a MOOC covering parts of the book[0]. The course is archived on edX, and the videos are on YouTube[1]. It was fun starting from a super simple functional language and building to a dataflow functional language by the end.