(motive : String × Lean.Doc.Ref✝ String → Sort u_1) →
  (x : String × Lean.Doc.Ref✝¹ String) →
    ((fst content : String) →
        (location : Lean.Syntax) →
          (seen : Bool) → motive (fst, { content := content, location := location, seen := seen })) →
      motive x