context take a &mut WeakDom to simplify external business

src/context.rs

@@ -10,16 +10,13 @@ pub fn class_is_a(class:&str,superclass:&str)->bool{
 	)
 }
 
-pub struct Context{
-	pub(crate)dom:WeakDom,
+pub struct Context<'a>{
+	pub(crate)dom:&'a mut WeakDom,
 }
 
-impl Context{
-	pub const fn new(dom:WeakDom)->Self{
-		Self{dom}
-	}
-	pub fn into_inner(self)->WeakDom{
-		self.dom
+impl Context<'_>{
+	pub fn new(dom:&mut WeakDom)->Context<'_>{
+		Context{dom}
 	}
 	/// Creates an iterator over all items of a particular class.
 	pub fn superclass_iter<'a>(&'a self,superclass:&'a str)->impl Iterator<Item=Ref>+'a{