Index: jsd_xpc.cpp
===================================================================
RCS file: /cvsroot/mozilla/js/jsd/jsd_xpc.cpp,v
retrieving revision 1.72
diff -u -r1.72 jsd_xpc.cpp
--- jsd_xpc.cpp
+++ jsd_xpc.cpp
@@ -2276,6 +2339,41 @@
     return NS_OK;
 }
 
+NS_IMETHODIMP
+jsdValue::GetSize(PRInt32 *aSize)
+{
+    ASSERT_VALID_EPHEMERAL;
+    jsval val;
+
+    val = JSD_GetValueWrappedJSVal (mCx, mValue);
+
+    if (JSVAL_IS_NULL(val))
+        *aSize = 4;
+    else if (JSVAL_IS_BOOLEAN(val))
+        *aSize = 4;
+    else if (JSVAL_IS_DOUBLE(val))
+        *aSize = 8;
+    else if (JSVAL_IS_INT(val))
+        *aSize = 4;
+    else if (JSVAL_IS_STRING(val))
+        *aSize = 2 * JS_GetStringLength(JSVAL_TO_STRING(val));
+    else if (JSVAL_IS_VOID(val))
+        *aSize = 4;
+    else {
+        JSContext  *cx  = JSD_GetDefaultJSContext (mCx);
+        if (JSD_IsValueFunction (mCx, mValue))
+            *aSize = JS_GetFunctionTotalSize(cx, (JSFunction*)JSVAL_TO_OBJECT(val));
+        else if (JSVAL_IS_OBJECT(val))
+            *aSize = JS_GetObjectTotalSize(cx, JSVAL_TO_OBJECT(val));
+        else {
+            *aSize = 0;
+            return NS_ERROR_UNEXPECTED;
+        }
+    }
+
+    return NS_OK;
+}
+
 /******************************************************************************
  * debugger service implementation
  ******************************************************************************/
Index: idl/jsdIDebuggerService.idl
===================================================================
RCS file: /cvsroot/mozilla/js/jsd/idl/jsdIDebuggerService.idl,v
retrieving revision 1.32
diff -u -r1.32 idl/jsdIDebuggerService.idl
--- idl/jsdIDebuggerService.idl
+++ idl/jsdIDebuggerService.idl
@@ -1143,6 +1149,12 @@
      * defined error code.
      */
     void getWrappedValue();
+
+    /**
+     * Retrieves the size of the object (including space required for slots,
+     * but excluding space required by objects referenced by the object).
+     */
+    readonly attribute long size;
 };
 
 /**