RDF.Literal.datatype-question-mark
You're seeing just the function
datatype-question-mark
, go back to RDF.Literal module for more information.
Returns if the given value is a RDF.Literal
or RDF.Literal.Datatype
struct.
If you simply want to check for a RDF.Literal
use pattern matching or RDF.literal?/1
.
This function is a bit slower than those and most of the time only needed when
implementing RDF.Literal.Datatype
s where you have to deal with the raw,
i.e. unwrapped RDF.Literal.Datatype
structs.