diff --git a/dw/alignedtablecell.cc b/dw/alignedtablecell.cc
index 04d0701..4e8f07f 100644
--- a/dw/alignedtablecell.cc
+++ b/dw/alignedtablecell.cc
@@ -27,13 +27,13 @@ using namespace lout;
 
 namespace dw {
 
-int AlignedTableCell::CLASS_ID = -1;
+std::intptr_t AlignedTableCell::CLASS_ID = -1;
 
 AlignedTableCell::AlignedTableCell (AlignedTableCell *ref, bool limitTextWidth):
    AlignedTextblock (limitTextWidth)
 {
    DBG_OBJ_CREATE ("dw::AlignedTableCell");
-   registerName ("dw::AlignedTableCell", &CLASS_ID);
+   registerName ("dw::AlignedTableCell", typeid(*this), &CLASS_ID);
 
    /** \bug ignoreLine1OffsetSometimes does not work? */
    //ignoreLine1OffsetSometimes = true;
diff --git a/dw/alignedtablecell.hh b/dw/alignedtablecell.hh
index 820256c..ad235d9 100644
--- a/dw/alignedtablecell.hh
+++ b/dw/alignedtablecell.hh
@@ -33,7 +33,7 @@ protected:
    void setMaxValue (int maxValue, int value);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    AlignedTableCell(AlignedTableCell *ref, bool limitTextWidth);
    ~AlignedTableCell();
diff --git a/dw/alignedtextblock.cc b/dw/alignedtextblock.cc
index 2f530d6..81fa51d 100644
--- a/dw/alignedtextblock.cc
+++ b/dw/alignedtextblock.cc
@@ -58,13 +58,13 @@ void AlignedTextblock::List::unref(int pos)
       delete this;
 }
 
-int AlignedTextblock::CLASS_ID = -1;
+std::intptr_t AlignedTextblock::CLASS_ID = -1;
 
 AlignedTextblock::AlignedTextblock (bool limitTextWidth):
    Textblock (limitTextWidth)
 {
    DBG_OBJ_CREATE ("dw::AlignedTextblock");
-   registerName ("dw::AlignedTextblock", &CLASS_ID);
+   registerName ("dw::AlignedTextblock", typeid(*this), &CLASS_ID);
 }
 
 void AlignedTextblock::setRefTextblock (AlignedTextblock *ref)
diff --git a/dw/alignedtextblock.hh b/dw/alignedtextblock.hh
index c0b392d..a499ad9 100644
--- a/dw/alignedtextblock.hh
+++ b/dw/alignedtextblock.hh
@@ -51,7 +51,7 @@ protected:
    void updateValue ();
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    ~AlignedTextblock();
 };
diff --git a/dw/image.cc b/dw/image.cc
index 2c4f632..df04615 100644
--- a/dw/image.cc
+++ b/dw/image.cc
@@ -131,12 +131,12 @@ int ImageMapsList::link (object::Object *key, int x, int y)
 
 // ----------------------------------------------------------------------
 
-int Image::CLASS_ID = -1;
+std::intptr_t Image::CLASS_ID = -1;
 
 Image::Image(const char *altText)
 {
    DBG_OBJ_CREATE ("dw::Image");
-   registerName ("dw::Image", &CLASS_ID);
+   registerName ("dw::Image", typeid(*this), &CLASS_ID);
    this->altText = altText ? dStrdup (altText) : NULL;
    altTextWidth = -1; // not yet calculated
    buffer = NULL;
diff --git a/dw/image.hh b/dw/image.hh
index fab660b..b1d8e7d 100644
--- a/dw/image.hh
+++ b/dw/image.hh
@@ -145,7 +145,7 @@ protected:
    //core::Iterator *iterator (Content::Type mask, bool atEnd);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    Image(const char *altText);
    ~Image();
diff --git a/dw/listitem.cc b/dw/listitem.cc
index a720630..23aa5e0 100644
--- a/dw/listitem.cc
+++ b/dw/listitem.cc
@@ -25,13 +25,13 @@
 
 namespace dw {
 
-int ListItem::CLASS_ID = -1;
+std::intptr_t ListItem::CLASS_ID = -1;
 
 ListItem::ListItem (ListItem *ref, bool limitTextWidth):
    AlignedTextblock (limitTextWidth)
 {
    DBG_OBJ_CREATE ("dw::ListItem");
-   registerName ("dw::ListItem", &CLASS_ID);
+   registerName ("dw::ListItem", typeid(*this), &CLASS_ID);
    setRefTextblock (ref);
 }
 
diff --git a/dw/listitem.hh b/dw/listitem.hh
index eca052f..e0b7780 100644
--- a/dw/listitem.hh
+++ b/dw/listitem.hh
@@ -13,7 +13,7 @@ protected:
    void setMaxValue (int maxValue, int value);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    ListItem(ListItem *ref, bool limitTextWidth);
    ~ListItem();
diff --git a/dw/oofawarewidget.cc b/dw/oofawarewidget.cc
index 139d3a6..d92bff4 100644
--- a/dw/oofawarewidget.cc
+++ b/dw/oofawarewidget.cc
@@ -38,12 +38,12 @@ const char *OOFAwareWidget::OOFM_NAME[NUM_OOFM] = {
    "FLOATS", "ABSOLUTE", "RELATIVE", "FIXED"
 };
 
-int OOFAwareWidget::CLASS_ID = -1;
+std::intptr_t OOFAwareWidget::CLASS_ID = -1;
 
 OOFAwareWidget::OOFAwareWidget ()
 {
    DBG_OBJ_CREATE ("dw::oof::OOFAwareWidget");
-   registerName ("dw::oof::OOFAwareWidget", &CLASS_ID);
+   registerName ("dw::oof::OOFAwareWidget", typeid(*this), &CLASS_ID);
 
    for (int i = 0; i < NUM_OOFM; i++) {
       oofContainer[i] = NULL;
diff --git a/dw/oofawarewidget.hh b/dw/oofawarewidget.hh
index 5e67ad0..76f4412 100644
--- a/dw/oofawarewidget.hh
+++ b/dw/oofawarewidget.hh
@@ -195,7 +195,7 @@ public:
       SL_START, SL_BACKGROUND, SL_SC_BOTTOM, SL_IN_FLOW, SL_OOF_REF,
       SL_OOF_CONT, SL_SC_TOP, SL_END };
 
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    OOFAwareWidget ();
    ~OOFAwareWidget ();
diff --git a/dw/regardingborder.cc b/dw/regardingborder.cc
index c3f04bc..c5ba83c 100644
--- a/dw/regardingborder.cc
+++ b/dw/regardingborder.cc
@@ -23,12 +23,12 @@
 
 namespace dw {
 
-int RegardingBorder::CLASS_ID = -1;
+std::intptr_t RegardingBorder::CLASS_ID = -1;
 
 RegardingBorder::RegardingBorder ()
 {
    DBG_OBJ_CREATE ("dw::RegardingBorder");
-   registerName ("dw::RegardingBorder", &CLASS_ID);
+   registerName ("dw::RegardingBorder", typeid(*this), &CLASS_ID);
 }
 
 RegardingBorder::~RegardingBorder ()
diff --git a/dw/regardingborder.hh b/dw/regardingborder.hh
index e2348c9..cfb2aad 100644
--- a/dw/regardingborder.hh
+++ b/dw/regardingborder.hh
@@ -13,7 +13,7 @@ namespace dw {
 class RegardingBorder: public oof::OOFAwareWidget
 {
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    RegardingBorder ();
    ~RegardingBorder ();
diff --git a/dw/ruler.cc b/dw/ruler.cc
index 0de6bc6..ae7cc06 100644
--- a/dw/ruler.cc
+++ b/dw/ruler.cc
@@ -26,12 +26,12 @@
 
 namespace dw {
 
-int Ruler::CLASS_ID = -1;
+std::intptr_t Ruler::CLASS_ID = -1;
 
 Ruler::Ruler ()
 {
    DBG_OBJ_CREATE ("dw::Ruler");
-   registerName ("dw::Ruler", &CLASS_ID);
+   registerName ("dw::Ruler", typeid(*this), &CLASS_ID);
 }
 
 Ruler::~Ruler ()
diff --git a/dw/ruler.hh b/dw/ruler.hh
index 74e163f..b6c7cc9 100644
--- a/dw/ruler.hh
+++ b/dw/ruler.hh
@@ -30,7 +30,7 @@ protected:
                                    core::GettingWidgetAtPointContext *context);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    Ruler ();
    ~Ruler ();
diff --git a/dw/simpletablecell.cc b/dw/simpletablecell.cc
index 3b37d8b..4beb111 100644
--- a/dw/simpletablecell.cc
+++ b/dw/simpletablecell.cc
@@ -27,13 +27,13 @@ using namespace lout;
 
 namespace dw {
 
-int SimpleTableCell::CLASS_ID = -1;
+std::intptr_t SimpleTableCell::CLASS_ID = -1;
 
 SimpleTableCell::SimpleTableCell (bool limitTextWidth):
    Textblock (limitTextWidth)
 {
    DBG_OBJ_CREATE ("dw::SimpleTableCell");
-   registerName ("dw::SimpleTableCell", &CLASS_ID);
+   registerName ("dw::SimpleTableCell", typeid(*this), &CLASS_ID);
 }
 
 SimpleTableCell::~SimpleTableCell()
diff --git a/dw/simpletablecell.hh b/dw/simpletablecell.hh
index dc5ccaf..ed3525c 100644
--- a/dw/simpletablecell.hh
+++ b/dw/simpletablecell.hh
@@ -24,7 +24,7 @@ protected:
    bool adjustExtraSpaceWhenCorrectingRequisitionByOOF ();
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    SimpleTableCell (bool limitTextWidth);
    ~SimpleTableCell ();
diff --git a/dw/table.cc b/dw/table.cc
index edf5f96..14213d8 100644
--- a/dw/table.cc
+++ b/dw/table.cc
@@ -29,12 +29,12 @@ using namespace lout;
 namespace dw {
 
 bool Table::adjustTableMinWidth = true;
-int Table::CLASS_ID = -1;
+std::intptr_t Table::CLASS_ID = -1;
 
 Table::Table(bool limitTextWidth)
 {
    DBG_OBJ_CREATE ("dw::Table");
-   registerName ("dw::Table", &CLASS_ID);
+   registerName ("dw::Table", typeid(*this), &CLASS_ID);
    setButtonSensitive(false);
 
    this->limitTextWidth = limitTextWidth;
diff --git a/dw/table.hh b/dw/table.hh
index 1db9468..866ff85 100644
--- a/dw/table.hh
+++ b/dw/table.hh
@@ -492,7 +492,7 @@ protected:
    void removeChild (Widget *child);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    inline static void setAdjustTableMinWidth (bool adjustTableMinWidth)
    { Table::adjustTableMinWidth = adjustTableMinWidth; }
diff --git a/dw/textblock.cc b/dw/textblock.cc
index e7ae70e..78b1a9b 100644
--- a/dw/textblock.cc
+++ b/dw/textblock.cc
@@ -43,7 +43,7 @@ using namespace lout::unicode;
 
 namespace dw {
 
-int Textblock::CLASS_ID = -1;
+std::intptr_t Textblock::CLASS_ID = -1;
 
 Textblock::WordImgRenderer::WordImgRenderer (Textblock *textblock,
                                              int wordNo)
@@ -206,7 +206,7 @@ void Textblock::setStretchabilityFactor (int stretchabilityFactor)
 Textblock::Textblock (bool limitTextWidth, bool treatAsInline)
 {
    DBG_OBJ_CREATE ("dw::Textblock");
-   registerName ("dw::Textblock", &CLASS_ID);
+   registerName ("dw::Textblock", typeid(*this), &CLASS_ID);
    setButtonSensitive(true);
 
    hasListitemValue = false;
diff --git a/dw/textblock.hh b/dw/textblock.hh
index 6ec8469..30d18d8 100644
--- a/dw/textblock.hh
+++ b/dw/textblock.hh
@@ -864,7 +864,7 @@ protected:
    int getGeneratorRest (int oofmIndex);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    static void setPenaltyHyphen (int penaltyHyphen);
    static void setPenaltyHyphen2 (int penaltyHyphen2);
diff --git a/dw/ui.cc b/dw/ui.cc
index 3364cc4..9fd6add 100644
--- a/dw/ui.cc
+++ b/dw/ui.cc
@@ -32,12 +32,12 @@ namespace ui {
 using namespace lout;
 using namespace lout::object;
 
-int Embed::CLASS_ID = -1;
+std::intptr_t Embed::CLASS_ID = -1;
 
 Embed::Embed(Resource *resource)
 {
    DBG_OBJ_CREATE ("dw::core::ui::Embed");
-   registerName ("dw::core::ui::Embed", &CLASS_ID);
+   registerName ("dw::core::ui::Embed", typeid(*this), &CLASS_ID);
    this->resource = resource;
    resource->setEmbed (this);
    DBG_OBJ_ASSOC_CHILD (resource);
diff --git a/dw/ui.hh b/dw/ui.hh
index 14c7268..46bde3b 100644
--- a/dw/ui.hh
+++ b/dw/ui.hh
@@ -251,7 +251,7 @@ protected:
    bool buttonPressImpl (core::EventButton *event);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    Embed(Resource *resource);
    ~Embed();
diff --git a/dw/widget.cc b/dw/widget.cc
index 8eda39e..27e53d6 100644
--- a/dw/widget.cc
+++ b/dw/widget.cc
@@ -73,12 +73,12 @@ void Widget::WidgetImgRenderer::draw (int x, int y, int width, int height)
 // ----------------------------------------------------------------------
 
 bool Widget::adjustMinWidth = true;
-int Widget::CLASS_ID = -1;
+std::intptr_t Widget::CLASS_ID = -1;
 
 Widget::Widget ()
 {
    DBG_OBJ_CREATE ("dw::core::Widget");
-   registerName ("dw::core::Widget", &CLASS_ID);
+   registerName ("dw::core::Widget", typeid(*this), &CLASS_ID);
 
    DBG_OBJ_ASSOC_CHILD (&requisitionParams);
    DBG_OBJ_ASSOC_CHILD (&extremesParams);
diff --git a/dw/widget.hh b/dw/widget.hh
index 63425e9..9dbd9cd 100644
--- a/dw/widget.hh
+++ b/dw/widget.hh
@@ -458,7 +458,7 @@ private:
 
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    inline static void setAdjustMinWidth (bool adjustMinWidth)
    { Widget::adjustMinWidth = adjustMinWidth; }
diff --git a/lout/identity.cc b/lout/identity.cc
index 08f3722..db63f1a 100644
--- a/lout/identity.cc
+++ b/lout/identity.cc
@@ -31,11 +31,11 @@ namespace identity {
 using namespace object;
 using namespace container::typed;
 
-IdentifiableObject::Class::Class (IdentifiableObject::Class *parent, int id,
+IdentifiableObject::Class::Class (IdentifiableObject::Class *parent, const std::type_index id,
                                   const char *className)
+	: id( (std::intptr_t) id.name() )
 {
    this->parent = parent;
-   this->id = id;
    this->className = className;
 }
 
@@ -57,7 +57,7 @@ void IdentifiableObject::Class::intoStringBuffer(misc::StringBuffer *sb)
 
 std::map< std::string, std::unique_ptr< IdentifiableObject::Class > > IdentifiableObject::classesByName;
 
-std::vector< IdentifiableObject::Class * > IdentifiableObject::classesById;
+std::map< std::intptr_t, IdentifiableObject::Class * > IdentifiableObject::classesById;
 
 IdentifiableObject::Class *IdentifiableObject::currentlyConstructedClass;
 
@@ -79,13 +79,13 @@ void IdentifiableObject::intoStringBuffer(misc::StringBuffer *sb)
  * \brief This method must be called in the constructor for the sub class.
  *    See class comment for details.
  */
-void IdentifiableObject::registerName (const char *className, int *classId)
+void IdentifiableObject::registerName (const char *className, const std::type_index index, std::intptr_t *classId)
 {
    if (not classesByName.contains( className )) {
       classesByName.emplace( className,
-            std::make_unique< Class >( currentlyConstructedClass, classesById.size(), className ) );
+            std::make_unique< Class >( currentlyConstructedClass, index, className ) );
       auto *const klass= classesByName.at( className ).get();
-      classesById.push_back( klass );
+      classesById[ klass->id ]= klass;
       *classId = klass->id;
    }
    Class *const klass = classesByName.at( className ).get();
@@ -99,7 +99,7 @@ void IdentifiableObject::registerName (const char *className, int *classId)
  * \brief Returns, whether this class is an instance of the class, given by
  *    \em otherClassId, or of a sub class of this class.
  */
-bool IdentifiableObject::instanceOf (int otherClassId)
+bool IdentifiableObject::instanceOf (std::intptr_t otherClassId)
 {
    if (otherClassId == -1)
       // Other class has not been registered yet, while it should have been,
diff --git a/lout/identity.hh b/lout/identity.hh
index 3a14056..aea9952 100644
--- a/lout/identity.hh
+++ b/lout/identity.hh
@@ -2,6 +2,7 @@
 #define __LOUT_OBJECTX_HH__
 
 #include <memory>
+#include <typeindex>
 #include <vector>
 #include <map>
 
@@ -106,22 +107,22 @@ private:
    {
    public:
       Class *parent;
-      int id;
+      std::intptr_t id;
       const char *className;
 
-      Class (Class *parent, int id, const char *className);
+      Class (Class *parent, std::type_index id, const char *className);
 
       void intoStringBuffer(misc::StringBuffer *sb);
    };
 
    static std::map< std::string, std::unique_ptr< Class > > classesByName;
-   static std::vector< Class * > classesById;
+   static std::map< std::intptr_t, Class * > classesById;
    static Class *currentlyConstructedClass;
 
-   int classId;
+   std::intptr_t classId;
 
 protected:
-   void registerName (const char *className, int *classId);
+   void registerName (const char *className, std::type_index index, std::intptr_t *classId);
 
 public:
    IdentifiableObject ();
@@ -134,7 +135,7 @@ public:
     * This is rarely used, rather, tests with
     * identity::IdentifiableObject::instanceOf are done.
     */
-   int getClassId () { return classId; }
+   std::intptr_t getClassId () { return classId; }
 
    /**
     * \brief Return the name, under which the class of this object was
@@ -142,7 +143,7 @@ public:
     */
    const char *getClassName() { return classesById.at( classId )->className; }
 
-   bool instanceOf (int otherClassId);
+   bool instanceOf (std::intptr_t otherClassId);
 };
 
 } // namespace identity