An expression that identifies a shape by name, number, or id, using one of the following forms:

card.shapeID(posInteger)

card.shape(text)) // name

card.shape(posInteger) // number

background.shapeID(posInteger)

background.shape(text)) // name

background.shape(posInteger) // number

For example:

thisCard.shapeID(3)

thisCard.shape("rectangle")

thisCard.shape(1)

thisBackground.shape(2)