Add a with_imm_element_like() method.

… gives a generic element from a generic node.

src/components/script/dom/element.rs

@@ -120,12 +120,12 @@ pub enum ElementTypeId {
 // Element methods
 //
 
-impl<'self> ElementLike<'self> for Element {
-    fn get_local_name(&'self self) -> &'self str {
+impl ElementLike for Element {
+    fn get_local_name<'a>(&'a self) -> &'a str {
         self.tag_name.as_slice()
     }
 
-    fn get_attr(&'self self, name: &str) -> Option<&'self str> {
+    fn get_attr<'a>(&'a self, name: &str) -> Option<&'a str> {
         // FIXME: Need an each() that links lifetimes in Rust.
         for attr in self.attrs.iter() {
             // FIXME: only case-insensitive in the HTML namespace (as opposed to SVG, etc.)

src/components/script/dom/node.rs

@@ -25,7 +25,7 @@ use extra::arc::Arc;
 use js::jsapi::{JSObject, JSContext};
 use netsurfcss::util::VoidPtrLike;
 use newcss::complete::CompleteSelectResults;
-use servo_util::tree::{TreeNode, TreeNodeRef};
+use servo_util::tree::{TreeNode, TreeNodeRef, TreeNodeRefAsElement};
 use servo_util::range::Range;
 use gfx::display_list::DisplayList;
 
@@ -156,6 +156,14 @@ impl<View> TreeNodeRef<Node<View>> for AbstractNode<View> {
     }
 }
 
+impl<View> TreeNodeRefAsElement<Node<View>, Element> for AbstractNode<View> {
+    #[inline]
+    fn with_imm_element_like<R>(self, f: &fn(&Element) -> R) -> R {
+        self.with_imm_element(f)
+    }
+}
+
+
 impl<View> TreeNode<AbstractNode<View>> for Node<View> { }
 
 impl<'self, View> AbstractNode<View> {

src/components/util/tree.rs

@@ -250,6 +250,10 @@ pub trait TreeNodeRef<Node>: Clone {
     }
 }
 
+pub trait TreeNodeRefAsElement<Node, E: ElementLike>: TreeNodeRef<Node> {
+    fn with_imm_element_like<R>(self, f: &fn(&E) -> R) -> R;
+}
+
 fn gather<Node, Ref: TreeNodeRef<Node>>(cur: &Ref, refs: &mut ~[Ref],
                                         postorder: bool, prune: &fn(&Ref) -> bool) {
     // prune shouldn't mutate, so don't clone
@@ -326,7 +330,7 @@ pub trait TreeNode<Ref: TreeNodeRef<Self>> {
 }
 
 
-pub trait ElementLike<'self> {
-    fn get_local_name(&'self self) -> &'self str;
-    fn get_attr(&'self self, name: &str) -> Option<&'self str>;
+pub trait ElementLike {
+    fn get_local_name<'a>(&'a self) -> &'a str;
+    fn get_attr<'a>(&'a self, name: &str) -> Option<&'a str>;
 }