∀ {motive_1 : Lean.Xml.Element → Sort u} {motive_2 : Lean.Xml.Content → Sort u}
  {motive_3 : Array Lean.Xml.Content → Sort u} {motive_4 : List Lean.Xml.Content → Sort u} (t : Lean.Xml.Element)
  (F_1 : (t : Lean.Xml.Element) → t.below → motive_1 t) (F_2 : (t : Lean.Xml.Content) → t.below → motive_2 t)
  (F_3 : (t : Array Lean.Xml.Content) → Lean.Xml.Element.below_1 t → motive_3 t)
  (F_4 : (t : List Lean.Xml.Content) → Lean.Xml.Element.below_2 t → motive_4 t),
  t.brecOn F_1 F_2 F_3 F_4 = F_1 t (Lean.Xml.Element.brecOn.go t F_1 F_2 F_3 F_4).2