Notice that Literal does not include the outer literal/1 predicate. This means that instantiations of Literal cannot be used directly in other
Literal can have either of the following forms:
type(DatatypeIri,LexicalExpression)for typed literals
lang(LanguageTag,LexicalExpression)for language-tagged strings
- LexicalExpression for plain strings
library(semweb/rdf11) does bind Literal to full literal terms.