A Pseudo-component has the same attributes as ordinary schema component: a name, a namespace and a type. Current
implementation of Pseudo-components requires exact specifying the name and namespace for the new pseudo-component.
Sometimes it is not acceptable because they (name + namespace) can be unknown. It is implied that only type is known in
such cases. 
It is suggested to allow pseudo-elements with only type specified. They can be called anonymous pseudo-element. 
They should be represented in an XPath expression as asterisk wildcard sign. 
User can't map the anonymous pseudo-element itself, but he can use its internal nodes. That is why the feature is
applicable to elements only (attribute can't have internal structure).