Cyclic references lead to "too much recursion"

[s-tittel]

Hi and thanks for you great library.

When validating a data graph that contains cyclic references (e.g. hasPart / isPartOf relations), I get:

Uncaught (in promise) InternalError: too much recursion

Here is an example to reproduce: https://s.zazuko.com/SiL9iY

Edit: I would suggest employing a method similar to this.

[ktk]

Thanks for the report, pull-requests would be welcome.

You might also try out this one (not by us): https://github.com/rdf-ext/shacl-engine

[s-tittel]

Could you please review the PR?

[s-tittel]

thanks!