| | | <!ELEMENT connect EMPTY> <!ATTLIST connect input NMTOKEN #REQUIRED> <!ATTLIST connect name NMTOKEN #REQUIRED> <!ATTLIST connect output NMTOKEN #REQUIRED> <!ATTLIST connect procin NMTOKEN #REQUIRED> <!ATTLIST connect procout NMTOKEN #REQUIRED> <!ELEMENT constraint EMPTY> <!ATTLIST constraint max NMTOKEN #REQUIRED> <!ATTLIST constraint min NMTOKEN #REQUIRED> <!ATTLIST constraint proc NMTOKEN #REQUIRED> <!ELEMENT start EMPTY> <!ELEMENT toipipe ( ( | connect | constraint | start )* )> <!ATTLIST toipipe name NMTOKEN #IMPLIED> | <!ELEMENT EMPTY> <!ELEMENT ( ()* )> <!ATTLIST id NMTOKEN #REQUIRED> <!ATTLIST NMTOKEN #IMPLIED> <!ELEMENT EMPTY> <!ATTLIST NMTOKEN #IMPLIED>