RDF.Literal.Datatype.valid-question-mark

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

Specs

valid?(RDF.Literal.t() | literal() | any()) :: boolean()

Determines if a RDF.Literal has a proper value of the value space of its datatype.

This function also accepts literals of derived datatypes.