[gxml] Adding documentation examples

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 52da13cefcddcc11a4ef867d2d13429742a7a1f5
Author: Daniel Espinosa <esodan gmail com>
Date:   Thu Feb 2 17:42:24 2017 -0600

    Adding documentation examples

 gxml/GomNode.vala   |    4 ++-
 gxml/GomObject.vala |   58 +++++++++++++++++++++++++++++++-------------------
 2 files changed, 39 insertions(+), 23 deletions(-)
---
diff --git a/gxml/GomNode.vala b/gxml/GomNode.vala
index 6808491..0570c57 100644
--- a/gxml/GomNode.vala
+++ b/gxml/GomNode.vala
@@ -237,7 +237,9 @@ public class GXml.GomNode : Object,
     if (ns == nspace) return true;
     return false;
   }
-
+  /**
+   * Sets node's parent and checks for namespace conflics.
+   */
   internal void set_parent (DomNode node) throws GLib.Error {
     if (this is DomElement) {
       var e = (this as DomElement);
diff --git a/gxml/GomObject.vala b/gxml/GomObject.vala
index 657fc50..aeea6ba 100644
--- a/gxml/GomObject.vala
+++ b/gxml/GomObject.vala
@@ -332,29 +332,43 @@ public interface GXml.GomObject : GLib.Object,
    *
    * If Object's property has been set, this method overwrite it.
    *
+   * {{{
+   * class NodeA : GomObject {
+   *   construct { try { initialize ("NodeA"); } catch { warning ("Can't initialize); }
+   * }
+   * class NodeB : GomObject {
+   *   public NodeA node { get; set; }
+   * }
+   *
+   * var nb = new NodeB ();
+   * nb.create_instance_property ("node");
+   * assert (nb.node != null);
+   * }}}
+   *
    * Returns: true if property has been set and initialized, false otherwise.
    */
-   public bool create_instance_property (string name) {
-      var prop = find_object_property_name (name);
-      if (prop == null) return false;
-      Value v = Value (prop.value_type);
-      Object obj;
-      if (prop.value_type.is_a (typeof (GomCollection))) {
-        obj = Object.new (prop.value_type, "element", this);
-        v.set_object (obj);
-        set_property (prop.name, v);
-        return true;
-      }
-      if (prop.value_type.is_a (typeof (GomElement))) {
-        obj = Object.new (prop.value_type,"owner_document", this.owner_document);
-        try { this.append_child (obj as GomElement); }
-        catch (GLib.Error e) {
-          warning (_("Error while atemting to instantiate property object: %s").printf (e.message));
-        }
-        v.set_object (obj);
-        set_property (prop.name, v);
-        return true;
+  public bool create_instance_property (string name) {
+    var prop = find_object_property_name (name);
+    if (prop == null) return false;
+    Value v = Value (prop.value_type);
+    Object obj;
+    if (prop.value_type.is_a (typeof (GomCollection))) {
+      obj = Object.new (prop.value_type, "element", this);
+      v.set_object (obj);
+      set_property (prop.name, v);
+      return true;
+    }
+    if (prop.value_type.is_a (typeof (GomElement))) {
+      obj = Object.new (prop.value_type,"owner_document", this.owner_document);
+      try { this.append_child (obj as GomElement); }
+      catch (GLib.Error e) {
+        warning (_("Error while atemting to instantiate property object: %s").printf (e.message));
+        return false;
       }
-      return false;
-   }
+      v.set_object (obj);
+      set_property (prop.name, v);
+      return true;
+    }
+    return false;
+  }
 }