Some of the Object::equals now are const correct.

There's more to do.

Why make this const-correct, instead of ditch it?  Because whatever
I replace it with has to be ready for const correctness.

dw/iterator.cc

@@ -47,15 +47,17 @@ Iterator::~Iterator()
 {
 }
 
-bool Iterator::equals (Object *other)
+bool
+Iterator::equals( const Object *const other ) const
 {
-   Iterator *otherIt = (Iterator*)other;
+   Iterator *const otherIt = const_cast< Iterator * >( dynamic_cast< const Iterator * >( other ) );
    return
       this == otherIt ||
-      (getWidget() == otherIt->getWidget() && compareTo(otherIt) == 0);
+      (const_cast< Iterator * >( this )->getWidget() == otherIt->getWidget() && const_cast< Iterator * >( this )->compareTo(otherIt) == 0);
 }
 
-void Iterator::intoStringBuffer(misc::StringBuffer *sb)
+void
+Iterator::intoStringBuffer(misc::StringBuffer *sb) const
 {
    sb->append ("{ widget = ");
    //widget->intoStringBuffer (sb);
@@ -68,7 +70,7 @@ void Iterator::intoStringBuffer(misc::StringBuffer *sb)
    Content::maskIntoStringBuffer (mask, sb);
 
    sb->append (", content = ");
-   Content::intoStringBuffer (&content, sb);
+   Content::intoStringBuffer (const_cast< Content * >( &content ), sb);
 
    sb->append (" }");
 }

dw/iterator.hh

@@ -30,8 +30,8 @@ private:
    Content::Type mask;
 
 public:
-   bool equals (Object *other);
+   bool equals (const Object *other) const override;
-   void intoStringBuffer(lout::misc::StringBuffer *sb);
+   void intoStringBuffer(lout::misc::StringBuffer *sb) const override;
 
    inline Widget *getWidget () { return widget; }
    inline Content *getContent () { return &content; }

dw/style.cc

@@ -155,7 +155,7 @@ bool StyleAttrs::sizeDiffs (StyleAttrs *otherStyle)
    return false;
 }
 
-bool StyleAttrs::equals (object::Object *other) {
+bool StyleAttrs::equals (const object::Object *other) const {
    StyleAttrs *otherAttrs = (StyleAttrs *) other;
 
    return this == otherAttrs ||
@@ -398,7 +398,7 @@ void Style::copyAttrs (StyleAttrs *attrs)
 
 // ----------------------------------------------------------------------
 
-bool FontAttrs::equals(object::Object *other)
+bool FontAttrs::equals(const object::Object *other) const
 {
    FontAttrs *otherAttrs = (FontAttrs*)other;
    return
@@ -456,7 +456,7 @@ bool Font::exists (Layout *layout, const char *name)
 
 // ----------------------------------------------------------------------
 
-bool ColorAttrs::equals(object::Object *other)
+bool ColorAttrs::equals(const object::Object *other) const
 {
    ColorAttrs *oc = (ColorAttrs*)other;
    return this == oc || (color == oc->color);

dw/style.hh

@@ -508,7 +508,7 @@ public:
    int top, right, bottom, left;
 
    inline void setVal(int val) { top = right = bottom = left = val; }
-   inline bool equals (Box *other) {
+   inline bool equals (const Box *other) const {
       return top == other->top &&
          right == other->right &&
          bottom == other->bottom &&
@@ -603,7 +603,7 @@ public:
    inline bool hasBackground ()
    { return backgroundColor != NULL || backgroundImage != NULL; }
 
-   bool equals (lout::object::Object *other);
+   bool equals (const lout::object::Object *other) const override;
    int hashValue ();
 };
 
@@ -688,7 +688,7 @@ public:
    FontVariant fontVariant;
    FontStyle style;
 
-   bool equals(lout::object::Object *other);
+   bool equals(const lout::object::Object *other) const override;
    int hashValue();
 };
 
@@ -742,7 +742,7 @@ public:
 
    inline int getColor () { return color; }
 
-   bool equals(lout::object::Object *other);
+   bool equals(const lout::object::Object *other) const override;
    int hashValue();
 };
 

lout/container.cc

@@ -313,7 +313,7 @@ int List::size ()
    return numElements;
 }
 
-bool List::equals(Object *other)
+bool List::equals(const Object *other) const
 {
    List *otherList = (List*)other;
    Node *node1 = first, *node2 = otherList->first;

lout/container.hh

@@ -242,7 +242,7 @@ public:
    List(bool ownerOfObjects);
    ~List();
 
-   bool equals(Object *other);
+   bool equals(const Object *other) const override;
    int hashValue();
 
    int size ();
@@ -451,8 +451,8 @@ public:
    Collection () { this->base = NULL; }
    ~Collection () { if (this->base) delete this->base; }
 
-   bool equals(Object *other)
+   bool equals(const Object *other) const override
-   { return this->base->equals (((Collection<T>*)other)->base); }
+   { return this->base->equals (((const Collection<T>*)other)->base); }
 
    int hashValue() { return this->base->hashValue (); }
 

lout/object.cc

@@ -48,7 +48,8 @@ Object::~Object()
  * this makes casting of "other" safe. Typically, an implementation should
  * check this == other first, the caller can assume a fast implementation.
  */
-bool Object::equals(Object *other)
+bool
+Object::equals( const Object *const other ) const
 {
    misc::assertNotReached ();
    return false;
@@ -149,7 +150,7 @@ StandardComparator standardComparator;
 //    Pointer
 // -------------
 
-bool Pointer::equals(Object *other)
+bool Pointer::equals(const Object *other) const
 {
    return value == ((Pointer*)other)->value;
 }
@@ -187,7 +188,7 @@ void Pointer::intoStringBuffer(misc::StringBuffer *sb)
 //    Integer
 // -------------
 
-bool Integer::equals(Object *other)
+bool Integer::equals(const Object *other) const
 {
    return value == ((Integer*)other)->value;
 }
@@ -213,7 +214,7 @@ int Integer::compareTo(Comparable *other)
 //    Boolean
 // -------------
 
-bool Boolean::equals(Object *other)
+bool Boolean::equals(const Object *other) const
 {
    bool value2 = ((Boolean*)other)->value;
    // TODO Does "==" work?
@@ -239,7 +240,7 @@ int Boolean::compareTo(Comparable *other)
 //    ConstString
 // -----------------
 
-bool ConstString::equals(Object *other)
+bool ConstString::equals(const Object *other) const
 {
    ConstString *otherString = (ConstString*)other;
    return
@@ -317,7 +318,7 @@ PairBase::~PairBase()
       delete second;
 }
 
-bool PairBase::equals(Object *other)
+bool PairBase::equals(const Object *other) const
 {
    PairBase *otherPair = (PairBase*)other;
 
@@ -347,7 +348,7 @@ int PairBase::hashValue()
    return value;
 }
 
-void PairBase::intoStringBuffer(misc::StringBuffer *sb)
+void PairBase::intoStringBuffer(misc::StringBuffer *sb) const
 {
    sb->append("<pair: ");
 

lout/object.hh

@@ -4,6 +4,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include <utility>
+
 #include "misc.hh"
 
 namespace lout {
@@ -25,7 +27,8 @@ class Object
 {
 public:
    virtual ~Object();
-   virtual bool equals(Object *other);
+   virtual bool equals(const Object *other) const;
+   virtual bool equals(Object *other) final { return equals( &std::as_const( *other ) ); }
    virtual int hashValue();
    virtual Object *clone();
    virtual void intoStringBuffer(misc::StringBuffer *sb) const;
@@ -103,7 +106,7 @@ private:
 
 public:
    Pointer(void *value) { this->value = value; }
-   bool equals(Object *other);
+   bool equals(const Object *other) const override;
    int hashValue();
    void intoStringBuffer(misc::StringBuffer *sb);
    inline void *getValue() { return value; }
@@ -129,7 +132,7 @@ class Integer: public Comparable
 
 public:
    Integer(int value) { this->value = value; }
-   bool equals(Object *other);
+   bool equals(const Object *other) const override;
    int hashValue();
    void intoStringBuffer(misc::StringBuffer *sb);
    int compareTo(Comparable *other);
@@ -146,7 +149,7 @@ class Boolean: public Comparable
 
 public:
    Boolean(bool value) { this->value = value; }
-   bool equals(Object *other);
+   bool equals(const Object *other) const override;
    int hashValue();
    void intoStringBuffer(misc::StringBuffer *sb);
    int compareTo(Comparable *other);
@@ -166,7 +169,7 @@ protected:
 
 public:
    ConstString(const char *str) { this->str = str; }
-   bool equals(Object *other);
+   bool equals(const Object *other) const override;
    int hashValue();
    int compareTo(Comparable *other);
    void intoStringBuffer(misc::StringBuffer *sb);
@@ -201,9 +204,9 @@ public:
    PairBase(Object *first, Object *second);
    ~PairBase();
 
-   bool equals(Object *other);
+   bool equals(const Object *other) const override;
    int hashValue();
-   void intoStringBuffer(misc::StringBuffer *sb);
+   void intoStringBuffer(misc::StringBuffer *sb) const override;
    size_t sizeOf();
 };