JavaScriptCore/runtime/JSNotAnObject.h
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/runtime/JSNotAnObject.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef JSNotAnObject_h
+#define JSNotAnObject_h
+
+#include "JSObject.h"
+
+namespace JSC {
+
+    class JSNotAnObjectErrorStub : public JSObject {
+    public:
+        JSNotAnObjectErrorStub(ExecState* exec, bool isNull)
+            : JSObject(exec->globalData().notAnObjectErrorStubStructure)
+            , m_isNull(isNull)
+        {
+        }
+
+        bool isNull() const { return m_isNull; }
+
+    private:
+        virtual bool isNotAnObjectErrorStub() const { return true; }
+
+        bool m_isNull;
+    };
+    
+    // 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 JSObject {
+    public:
+        JSNotAnObject(ExecState* exec, JSNotAnObjectErrorStub* exception)
+            : JSObject(exec->globalData().notAnObjectStructure)
+            , m_exception(exception)
+        {
+        }
+
+        static PassRefPtr<Structure> createStructure(JSValue prototype)
+        {
+            return Structure::create(prototype, TypeInfo(ObjectType, StructureFlags), AnonymousSlotCount);
+        }
+
+     private:
+        
+        static const unsigned StructureFlags = OverridesGetOwnPropertySlot | OverridesMarkChildren | OverridesGetPropertyNames | JSObject::StructureFlags;
+
+        // JSValue methods
+        virtual JSValue toPrimitive(ExecState*, PreferredPrimitiveType) const;
+        virtual bool getPrimitiveNumber(ExecState*, double& number, JSValue&);
+        virtual bool toBoolean(ExecState*) const;
+        virtual double toNumber(ExecState*) const;
+        virtual UString toString(ExecState*) const;
+        virtual JSObject* toObject(ExecState*) const;
+
+        // Marking
+        virtual void markChildren(MarkStack&);
+
+        // JSObject methods
+        virtual bool getOwnPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
+        virtual bool getOwnPropertySlot(ExecState*, unsigned propertyName, PropertySlot&);
+        virtual bool getOwnPropertyDescriptor(ExecState*, const Identifier&, PropertyDescriptor&);
+
+        virtual void put(ExecState*, const Identifier& propertyName, JSValue, PutPropertySlot&);
+        virtual void put(ExecState*, unsigned propertyName, JSValue);
+
+        virtual bool deleteProperty(ExecState*, const Identifier& propertyName);
+        virtual bool deleteProperty(ExecState*, unsigned propertyName);
+
+        virtual void getOwnPropertyNames(ExecState*, PropertyNameArray&, EnumerationMode mode = ExcludeDontEnumProperties);
+
+        JSNotAnObjectErrorStub* m_exception;
+    };
+
+} // namespace JSC
+
+#endif // JSNotAnObject_h