RDF.Term.equal_value-question-mark
You're seeing just the function
equal_value-question-mark
, go back to RDF.Term module for more information.
Tests for equality of values.
Non-RDF terms are tried to be coerced via RDF.Term.coerce/1
before comparison.
Returns nil
if the given terms are not comparable.
see http://www.w3.org/TR/rdf-sparql-query/#func-RDFterm-equal and the value equality semantics of the different literal datatypes here: https://www.w3.org/TR/sparql11-query/#OperatorMapping