∀ {α : Type} {decls1 decls2 : Array (Std.Sat.AIG.Decl α)} (size_le : decls1.size ≤ decls2.size),
  (∀ (idx : ℕ) (h : idx < decls1.size), decls2[idx] = decls1[idx]) → Std.Sat.AIG.IsPrefix decls1 decls2