Attribute definintion flag bitmask. Derived from Mask.

• Mask

 Attribute is a pointer.
 If bit private is set, it is an absolute pointer, and
 only valid in the owner process.
 If private is not set, it is a pool relative pointer, which
 can be translated to all processes.

 Attribute is an array.
 The size of the array is stored in the Element attribute.

 Not yet implemented.

 Attribute can be casted.

 State.
 Value is only valid in runtime, and can not
 be set in the development environment.

 Constant value.

 Attribute is not valid in runtime, though it resides
 in the runtime body.

 The DevBody contains an corresponding attribute.

 Not yet implemented.

 The attribute can be written without write privileges.

 The value of the attribute can not be changed in the
 configurator.

 The attribute is invisible in the navigator.

 Not yet implemented.

 Input can not be inverted.
 Used for $Input attributes in function objects.

 Input or output pin can not be removed.
 Used for $Input and $Output attributes in function objects.

 Not yet implemented.

 Attribute has read only access.
 If attribute is a pointer, the pointer can only be used by the
 owner process.

 The attribute is an attribute object, i.e it is defined
 by a class.
 The ClassId for the class is stored in the TypeRef attribute.

 The attribute defines a superclass.
 A superclass attribute i the first attribute in RtBody,
 and is named "Super".
 The ClassId for the superclass is stored in the TypeRef attribute.

 Attribute is a buffer attribute.

 The value of the attriute is not stored in wb_load files.

 The value of the attribute is always stored in wb_load files.

 The Attribute can be disabled.

 The Attribute is hidden in runtime.

 The Attribute is created in this session.

 The attribute value is hidden in the configurator.