R2RML mappings with RML functions

[namedgraph]

Issue type: ❓ Question

Hi. We have some YARRRML mappings that we export as RML for use with a custom RMLMapper implementation.
Now we would like to reuse the mappings as R2RML and feed them to ontop.
ontop doesn't support the RML functions we use in our mappings however. What's the course of action in this case? What can we replace those functions with, and how?

[bjdmeest]

You could have a look at how FunMap does it: https://github.com/SDM-TIB/FunMap
preprocess the functions and add them as additional key/values in your intermediate dataset, and adjust the mappings to remove the functions and replace them with the keys you used during preprocessing