- DOCUMENT@0..29
    - INTERFACE_TYPE_EXTENSION@0..29
        - extend_KW@0..6 "extend"
        - WHITESPACE@6..7 " "
        - interface_KW@7..16 "interface"
        - WHITESPACE@16..17 " "
        - NAME@17..29
            - IDENT@17..29 "ValuedEntity"
- ERROR@29:29 "exptected an Implements Interfaces, Directives, or a Fields Definition" EOF
