{pu : Lean.Compiler.LCNF.Purity} →
  {motive_1 : Lean.Compiler.LCNF.Alt pu → Sort u} →
    (t : Lean.Compiler.LCNF.Alt pu) →
      t.ctorIdx = 0 →
        ((ctorName : Lean.Name) →
            (params : Array (Lean.Compiler.LCNF.Param pu)) →
              (code : Lean.Compiler.LCNF.Code pu) →
                (h : pu = Lean.Compiler.LCNF.Purity.pure) →
                  motive_1 (Lean.Compiler.LCNF.Alt.alt ctorName params code h)) →
          motive_1 t