|
|
|
use rand::random;
|
|
|
|
use rio_api::model as rio;
|
|
|
|
use std::fmt;
|
|
|
|
use std::io::Write;
|
|
|
|
use std::str;
|
|
|
|
|
|
|
|
/// A RDF [blank node](https://www.w3.org/TR/rdf11-concepts/#dfn-blank-node).
|
|
|
|
///
|
|
|
|
/// This implementation enforces that the blank node id is a uniquely generated ID to easily ensure
|
|
|
|
/// that it is not possible for two blank nodes to share an id.
|
|
|
|
///
|
|
|
|
/// The common way to create a new blank node is to use the `Default::default` trait method.
|
|
|
|
///
|
|
|
|
/// The default string formatter is returning a N-Triples, Turtle and SPARQL compatible representation.
|
|
|
|
/// `BlankNode::default().to_string()` should return something like `_:00112233445566778899aabbccddeeff`
|
|
|
|
///
|
|
|
|
#[derive(Eq, PartialEq, Ord, PartialOrd, Debug, Clone, Copy, Hash)]
|
|
|
|
pub struct BlankNode {
|
|
|
|
id: u128,
|
|
|
|
str: [u8; 32],
|
|
|
|
}
|
|
|
|
|
|
|
|
impl BlankNode {
|
|
|
|
/// Creates a blank node from a unique id
|
|
|
|
pub(crate) fn new_from_unique_id(id: u128) -> Self {
|
|
|
|
let mut str = [0; 32];
|
|
|
|
write!(&mut str[..], "{:x}", id).unwrap();
|
|
|
|
Self { id, str }
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Returns the underlying ID of this blank node
|
|
|
|
pub fn as_str(&self) -> &str {
|
|
|
|
str::from_utf8(&self.str).unwrap()
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Returns the underlying ID of this blank node
|
|
|
|
pub(crate) const fn id(&self) -> u128 {
|
|
|
|
self.id
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl fmt::Display for BlankNode {
|
|
|
|
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
|
|
rio::BlankNode::from(self).fmt(f)
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl Default for BlankNode {
|
|
|
|
/// Builds a new RDF [blank node](https://www.w3.org/TR/rdf11-concepts/#dfn-blank-node) with a unique id
|
|
|
|
fn default() -> Self {
|
|
|
|
Self::new_from_unique_id(random::<u128>())
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl<'a> From<&'a BlankNode> for rio::BlankNode<'a> {
|
|
|
|
fn from(node: &'a BlankNode) -> Self {
|
|
|
|
rio::BlankNode { id: node.as_str() }
|
|
|
|
}
|
|
|
|
}
|