internal DbgSimpleSymbol(DbgEngDebugger debugger,
                          string name,
                          DbgNamedTypeInfo type,
                          DbgRegisterInfoBase register,
                          DbgSymbol parent)
     : this(debugger, name, type, register)
 {
     Parent = parent;
 } // end constructor
        } // end constructor

        internal DbgSimpleSymbol(DbgEngDebugger debugger,
                                 string name,
                                 DbgNamedTypeInfo type,
                                 DbgRegisterInfoBase register)
            : this(debugger, name, type)
        {
            if (null == register)
            {
                throw new ArgumentNullException("register");
            }

            m_register = register;
        } // end constructor