WIP: Start implementing precondition errors

crates/dav/src/xml/href.rs

@@ -0,0 +1,14 @@
+use derive_more::From;
+use rustical_xml::{XmlDeserialize, XmlSerialize};
+
+#[derive(XmlDeserialize, XmlSerialize, Debug, Clone, From, PartialEq)]
+pub struct HrefElement {
+    #[xml(ns = "crate::namespace::NS_DAV")]
+    pub href: String,
+}
+
+impl HrefElement {
+    pub fn new(href: String) -> Self {
+        Self { href }
+    }
+}