47 lines
1.2 KiB
Rust
47 lines
1.2 KiB
Rust
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use oxigraph::model::{NamedNode, Quad, Term};
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use oxigraph::model::vocab::{rdf, xsd};
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fn quad_to_term(quad: &Quad) -> &Term {
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&quad.object
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}
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fn term_to_named_node(term: &Term) -> Option<&NamedNode> {
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if let Term::NamedNode(node) = term {
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Some(node)
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} else {
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None
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}
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}
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fn term_to_string(term: &Term) -> Option<&str> {
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if let Term::Literal(literal) = term {
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match literal.datatype() {
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xsd::STRING | xsd::NORMALIZED_STRING | rdf::LANG_STRING | rdf::DIR_LANG_STRING => {
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Some(literal.value())
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}
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_ => None,
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}
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} else {
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None
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}
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}
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fn term_to_boolean(term: &Term) -> Option<bool> {
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if let Term::Literal(literal) = term {
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if literal.datatype() == xsd::BOOLEAN {
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literal.value().parse().ok()
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} else {
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None
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}
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} else {
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None
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}
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}
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fn term_to_u64(term: &Term) -> Option<u64> {
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if let Term::Literal(literal) = term &&
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literal.datatype() == xsd::NON_NEGATIVE_INTEGER {
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let value: u64 = literal.value().parse().expect("Failed to parse u64 from ontology. It ought to be a non-negative integer.");
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Some(value)
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} else { None }
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}
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