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

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...	...	@@ -1,40 +8,32 @@
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	8	### Data Structure Style
9	9
10		- struct Square {
	3	+ type Square struct {
11	11	length float
12	12	}
13	13
14		- struct Circle {
	7	+ type Circle struct {
15	15	radius float
16	16	}
17	17
18		- function Circumference(g Object) float {
	11	+ func Area(g GeometricObject) float {
19	19	switch type(g):
20	20	case Square:
	14	+ return g.length * g.length
	15	+ case Circle:
	16	+ return PI * g.radius * g.radius
	17	+ }
	18	+
	19	+ func Circumference(g GeometricObject) float {
	20	+ switch type(g):
	21	+ case Square:
21	21	return 4 * g.length
22	22	case Circle:
23	23	return 2 * PI * g.radius
24	24	}
25	25
26		-1. Adding a function Area() with the same anatomy as Circumference() is easy, since it only requires adding new code.
27		-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.
28		-
29		-####
30		-
31	31	#### Object-Oriented Style
32	32
33		- interface GeometricObject {
34		- Circumference() float
35		- }
36		-
37		- class Square implements GeometricObject {
	29	+ class Square {
38	38	length float
39	39
40	40	constructor(length float) {
...	...	@@ -41,12 +41,16 @@
41	41	this.length = length
42	42	}
43	43
	36	+ func Area() float {
	37	+ return this.length * this.length
	38	+ }
	39	+
44	44	func Circumference() float {
45	45	return 4 * this.length
46	46	}
47	47	}
48	48
49		- class Circle implements GeometricObject {
	45	+ class Circle {
50	50	radius float
51	51
52	52	constructor(radius float) {
...	...	@@ -53,6 +53,10 @@
53	53	this.radius = radius
54	54	}
55	55
	52	+ func Area() float {
	53	+ return PI * this.radius * this.radius
	54	+ }
	55	+
56	56	func Circumference() float {
57	57	return 2 * PI * this.radius
58	58	}