Instance accessors generate new quadrille instances derived from the original. These methods allow you to create modified versions while preserving the original quadrille’s state:

• clone(): Creates a shallow copy of the quadrille.
• row(row): Creates a new quadrille containing only the specified row.
• crop(row, col, width, height, wrap): Creates a new quadrille representing the rectangular region anchored at (row, col) with the given width and height.
• ring(row, col, dimension, wrap): Creates a new quadrille representing a ring of cells around the specified row and col with the given dimension.