Scala XML: Lazy sequences.

Author: Alex Simkin

.gitignore

@@ -1,5 +1,9 @@
 .gradle/
 .idea/
+.settings/
+bin/
 out/
 build/
+.project
+.classpath
 *.iml

xpath-to-xml-scala/src/main/scala/com/github/simy4/xpath/scala/navigator/ScalaXmlNavigator.scala

@@ -26,8 +26,10 @@ class ScalaXmlNavigator(xml: Root) extends Navigator[ScalaXmlNode] {
       val node = e.node
       val children = node.child
       val idx = children.size
-      val newElem = Elem(Some(element.getPrefix).filter(_.nonEmpty).orNull, element.getLocalPart, Null, node.scope,
-        minimizeEmpty = true)
+      val newElem = element.getPrefix match {
+        case pre if pre.nonEmpty => Elem(pre, element.getLocalPart, Null, node.scope, minimizeEmpty = true)
+        case _                   => Elem(null, element.getLocalPart, Null, node.scope, minimizeEmpty = true)
+      }
       e.node = node.copy(child = children :+ newElem)
       new Element(newElem, idx, e)
     case _          =>
@@ -56,7 +58,7 @@ class ScalaXmlNavigator(xml: Root) extends Navigator[ScalaXmlNode] {
       val parentNode = e.parent.node
       e.parent.node = parentNode.copy(child = parentNode.child patch (idx, Seq(copy, toCopy), 1))
       e.index += 1
-    case _                                         =>
+    case _          =>
       throw new XmlBuilderException(s"Unable to prepend copy to $node")
   }
   override def remove(node: ScalaXmlNode): Unit = node match {

xpath-to-xml-scala/src/main/scala/com/github/simy4/xpath/scala/navigator/scalaXmlNodes.scala

@@ -36,16 +36,16 @@ final class Root(override var node: Elem) extends Parent {
 }
 
 private[navigator] final class Element(private var _node: Elem, var index: Int,
-                                      override val parent: Parent) extends Parent {
+                                       override val parent: Parent) extends Parent {
   override def getName: QName = node match {
     case prefixed if null != prefixed.prefix => new QName(prefixed.namespace, prefixed.label, prefixed.prefix)
     case simple                              => new QName(simple.label)
   }
   override def getText: String = node.child.collect { case Text(t) => t }.mkString
   override def elements: Iterable[Element] = for {
-    (n, i) <- _node.child.zipWithIndex if !n.isAtom
+    (n, i) <- _node.child.view.zipWithIndex if !n.isAtom
   } yield new Element(n.asInstanceOf[Elem], i, this)
-  override def attributes: Iterable[Attribute] = _node.attributes map (new Attribute(_, this))
+  override def attributes: Iterable[Attribute] = _node.attributes.view map (new Attribute(_, this))
   override def node: Elem = _node
   override def node_=(elem: Elem): Unit = {
     parent.node = parent match {