∀ {x : Lean.IR.VarId} {n : ℕ} {c persistent : Bool} {b : Lean.IR.FnBody} {x_1 : Lean.IR.VarId} {n_1 : ℕ}
  {c_1 persistent_1 : Bool} {b_1 : Lean.IR.FnBody},
  Lean.IR.FnBody.dec x n c persistent b = Lean.IR.FnBody.dec x_1 n_1 c_1 persistent_1 b_1 →
    x = x_1 ∧ n = n_1 ∧ c = c_1 ∧ persistent = persistent_1 ∧ b = b_1