( :?names
& (     get
      $ ( "<Students>
  <Student Name=\"April\" Gender=\"F\" DateOfBirth=\"1989-01-02\" />
  <Student Name=\"Bob\" Gender=\"M\"  DateOfBirth=\"1990-03-04\" />
  <Student Name=\"Chad\" Gender=\"M\"  DateOfBirth=\"1991-05-06\" />
  <Student Name=\"Dave\" Gender=\"M\"  DateOfBirth=\"1992-07-08\">
    <Pet Type=\"dog\" Name=\"Rover\" />
  </Student>
  <Student DateOfBirth=\"1993-09-10\" Gender=\"F\" Name=\"&#x00C9;mily\" />
</Students>"
        , MEM
        , X
        , ML
        )
    :   ?
        ( ( Student
          .   (? (Name.?name) ?,)
            | ? (Name.?name) ?
          )
        & !names !name:?names
        & ~
        )
        ?
  | !names
  )
)