RDF.Statement.valid-question-mark

You're seeing just the function valid-question-mark, go back to RDF.Statement module for more information.

Specs

valid?(RDF.Triple.t() | RDF.Quad.t() | any()) :: boolean()

Checks if the given tuple is a valid RDF statement, i.e. RDF triple or quad.

The elements of a valid RDF statement must be RDF terms. On the subject position only IRIs and blank nodes allowed, while on the predicate and graph context position only IRIs allowed. The object position can be any RDF term.