{ρ : Type} →
  {pat : ρ} →
    {motive : String.Slice.Pattern.ForwardPattern pat → Sort u} →
      (t : String.Slice.Pattern.ForwardPattern pat) →
        ((startsWith : String.Slice → Bool) →
            (dropPrefix? : (s : String.Slice) → Option s.Pos) →
              motive { startsWith := startsWith, dropPrefix? := dropPrefix? }) →
          motive t