diff -u a/doc/src/snippets/code/src_gui_itemviews_qidentityproxymodel.cpp b/doc/src/snippets/code/src_gui_itemviews_qidentityproxymodel.cpp
--- a/doc/src/snippets/code/src_gui_itemviews_qidentityproxymodel.cpp     2012-03-15 00:01:52.000000000 +1000
+++ b/doc/src/snippets/code/src_gui_itemviews_qidentityproxymodel.cpp    2012-08-03 16:03:09.000000000 +1000
@@ -48,7 +48,7 @@
     m_formatString = formatString;
   }
 
-  QVariant data(const QModelIndex &index, int role)
+  QVariant data(const QModelIndex &index, int role) const
   {
     if (role != Qt::DisplayRole)
       return QIdentityProxyModel::data(index, role);