JavaScriptCore-1218.35.tar.gz

[apple/javascriptcore.git] / runtime / JSNotAnObject.h

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#ifndef JSNotAnObject_h
#define JSNotAnObject_h

#include "JSObject.h"

namespace JSC {

    // This unholy class is used to allow us to avoid multiple exception checks
    // in certain SquirrelFish bytecodes -- effectively it just silently consumes
    // any operations performed on the result of a failed toObject call.
    class JSNotAnObject : public JSNonFinalObject {
    private:
        JSNotAnObject(ExecState* exec)
            : JSNonFinalObject(exec->vm(), exec->vm().notAnObjectStructure.get())
        {
        }
        
    public:
        typedef JSNonFinalObject Base;

        static JSNotAnObject* create(ExecState* exec)
        {
            JSNotAnObject* object = new (NotNull, allocateCell<JSNotAnObject>(*exec->heap())) JSNotAnObject(exec);
            object->finishCreation(exec->vm());
            return object;
        }

        static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
        {
            return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), &s_info);
        }

        static const ClassInfo s_info;

     private:
        
        static const unsigned StructureFlags = OverridesGetOwnPropertySlot | InterceptsGetOwnPropertySlotByIndexEvenWhenLengthIsNotZero | OverridesGetPropertyNames | JSObject::StructureFlags;

        // JSValue methods
        static JSValue defaultValue(const JSObject*, ExecState*, PreferredPrimitiveType);

        // JSObject methods
        static bool getOwnPropertySlot(JSCell*, ExecState*, PropertyName, PropertySlot&);
        static bool getOwnPropertySlotByIndex(JSCell*, ExecState*, unsigned propertyName, PropertySlot&);
        static bool getOwnPropertyDescriptor(JSObject*, ExecState*, PropertyName, PropertyDescriptor&);

        static void put(JSCell*, ExecState*, PropertyName, JSValue, PutPropertySlot&);
        static void putByIndex(JSCell*, ExecState*, unsigned propertyName, JSValue, bool shouldThrow);

        static bool deleteProperty(JSCell*, ExecState*, PropertyName);
        static bool deletePropertyByIndex(JSCell*, ExecState*, unsigned propertyName);

        static void getOwnPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
    };

} // namespace JSC

#endif // JSNotAnObject_h