@[simp]

theorem String.Slice.beq_eq_true_iff {s t : Slice} : (s == t) = true ↔ s.copy = t.copy

@[simp]

theorem String.Slice.beq_eq_false_iff {s t : Slice} : (s == t) = false ↔ s.copy ≠ t.copy

theorem String.Slice.beq_eq_decide {s t : Slice} : (s == t) = decide (s.copy = t.copy)