Changes for page Code Example: Data Structure Style vs. Object Style

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1		-```
	1	+### Use Cases
	2	+
	3	+This example is intended to demonstrate the extensibility differences between data structures and objects by extending them with
	4	+
	5	+1. an Area() function (extending behavior)
	6	+1. a rectangle type (extending data type)
	7	+
	8	+### Data Structure Style
	9	+
	10	+ interface GeometricObject {}
	11	+
	12	+ class Square implements GeometricObject {
	13	+ length float
	14	+ }
	15	+
	16	+ class Circle implements GeometricObject {
	17	+ radius float
	18	+ }
	19	+
	20	+ function Circumference(g GeometricObject) float {
	21	+ switch type(g):
	22	+ case Square:
	23	+ return 4 * g.length
	24	+ case Circle:
	25	+ return 2 * PI * g.radius
	26	+ }
	27	+
	28	+1. Adding an Area() function with a very similar anatomy to Circumference() is easy because it only requires adding new code.
	29	+1. Adding a new datatype, Rectangle, is harder because it requires touching existing code, namely any functions like Circumference() or Area() that need to be enabled handle this datatype.
	30	+
	31	+####
	32	+
	33	+#### Object-Oriented Style
	34	+
	35	+ interface GeometricObject {
	36	+ Circumference() float
	37	+ }
	38	+
	39	+ class Square implements GeometricObject {
	40	+ length float
	41	+
	42	+ constructor(length float) {
	43	+ this.length = length
	44	+ }
	45	+
	46	+ func Circumference() float {
	47	+ return 4 * this.length
	48	+ }
	49	+ }
	50	+
	51	+ class Circle implements GeometricObject {
	52	+ radius float
	53	+
	54	+ constructor(radius float) {
	55	+ this.radius = radius
	56	+ }
	57	+
	58	+ func Circumference() float {
	59	+ return 2 * PI * this.radius
	60	+ }
	61	+ }
	62	+
	63	+1. Adding a function Area() to GeometricObject Interface is hard since all classes implementing
	64	+1. Adding a new datatype, Rectangle, is more difficult because it requires touching existing code, namely any functions like Circumference() or Area() that need to be enabled handle this datatype.
	65	+
	66	+### Conclusion
	67	+
	68	+asd
	69	+
	70	+