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

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...	...	@@ -1,30 +1,42 @@
1		-asd
	1	+### Use Cases
2	2
3		-```
4		-type Square struct {
5		- length float
6		-}
	3	+This example is intended to demonstrate the extensibility differences between data structures and objects by extending them with
7	7
8		-type Circle struct {
9		- length float
10		-}
	5	+1. an Area() function (extending behavior)
	6	+1. a rectangle type (extending data type)
11	11
12		-func Area(g GeometricObject) float {
13		- switch (g.type()):
14		- case Circle:
15		- return
16		- case Square:
17		- return ...
18		-}
	8	+### Data Structure Style
19	19
20		-func Circumference(g GeometricObject) float {
21		- ...
22		-}
23		-```
	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	+ }
24	24
	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	+
25	25	#### Object-Oriented Style
26	26
27		- class Square {
	35	+ interface GeometricObject {
	36	+ Circumference() float
	37	+ }
	38	+
	39	+ class Square implements GeometricObject {
28	28	length float
29	29
30	30	constructor(length float) {
...	...	@@ -31,16 +31,12 @@
31	31	this.length = length
32	32	}
33	33
34		- func Area() float {
35		- return this.length * this.length
36		- }
37		-
38	38	func Circumference() float {
39	39	return 4 * this.length
40	40	}
41	41	}
42	42
43		- class Circle {
	51	+ class Circle implements GeometricObject {
44	44	radius float
45	45
46	46	constructor(radius float) {
...	...	@@ -47,11 +47,16 @@
47	47	this.radius = radius
48	48	}
49	49
50		- func Area() float {
51		- return PI * this.radius * this.radius
52		- }
53		-
54	54	func Circumference() float {
55	55	return 2 * PI * this.radius
56	56	}
57	57	}
	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	+