xrust 1.2.4

Support for XPath and XSLT
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39

//! Support for XML Namespaces
//!
//! The [NamespaceMap] object represents a static mapping of prefix to namespace URI. Since namespaces don't change once they are declared, this object is usually Rc-shared.

use crate::value::Value;
use std::collections::hash_map::Iter;
use std::collections::HashMap;
use std::rc::Rc;

/// In some circumstances, a transformation must resolve a qualified name.
/// To do this, it must have a copy of the in-scope namespaces.
/// This type represents a mapping from prefix to Namespace URI.
/// The "None" prefix is for the default namespace.
pub struct NamespaceMap(HashMap<Option<Rc<Value>>, Rc<Value>>);
// TODO: should be default namespace be represented by the empty string prefix?

impl NamespaceMap {
    /// Create a new namespace mapping.
    pub fn new() -> Self {
        let mut map = HashMap::new();
        map.insert(
            Some(Rc::new(Value::from("xml"))),
            Rc::new(Value::from("http://www.w3.org/XML/1998/namespace")),
        );
        NamespaceMap(map)
    }
    /// Insert a mapping into the map.
    pub fn insert(&mut self, prefix: Option<Rc<Value>>, uri: Rc<Value>) -> Option<Rc<Value>> {
        self.0.insert(prefix, uri)
    }
    /// Lookup a prefix in the map, returning the namespace URI.
    pub fn get(&self, prefix: &Option<Rc<Value>>) -> Option<Rc<Value>> {
        self.0.get(prefix).cloned()
    }
    /// Iterate over mappings. Each item is a (prefix,namespace URI) pair.
    pub fn iter(&self) -> Iter<Option<Rc<Value>>, Rc<Value>> {
        self.0.iter()
    }
}