What is the difference between serialization and comparison?

Serialization is the process of converting an object into a stream of bytes for storage or transmission. The reverse process is deserialization.

Comparison (or comparison) is the process of determining relationships between two or more objects (equal, less, greater).

Examples:

Serialization to JSON:

import Foundation

struct Person: Encodable {
    let name: String
    let age: Int
}

let person = Person(name: "Alice", age: 30)
let encoder = JSONEncoder()

if let jsonData = try? encoder.encode(person),
   let jsonString = String(data: jsonData, encoding: .utf8) {
    // jsonString will be "{ \"name\":\"Alice\", \"age\":30 }"
    print(jsonString)
}

Object comparison:

struct Point: Equatable {
    let x: Int
    let y: Int
}

let p1 = Point(x: 1, y: 2)
let p2 = Point(x: 1, y: 2)
let p3 = Point(x: 3, y: 4)

// Equality comparison
print(p1 == p2) // true
print(p1 == p3) // false

// Comparison based on some criterion (e.g., sum of coordinates)
func comparePoints(p1: Point, p2: Point) -> ComparisonResult {
    let sum1 = p1.x + p1.y
    let sum2 = p2.x + p2.y

    if sum1 < sum2 {
        return .orderedAscending // p1 less than p2
    } else if sum1 > sum2 {
        return .orderedDescending // p1 greater than p2
    } else {
        return .orderedSame // p1 equal to p2
    }
}

print(comparePoints(p1: p1, p2: p3)) // .orderedAscending

Comparison table:

Characteristic	Serialization	Comparison
Purpose	Convert an object into a byte stream	Compare objects to determine order/equality
Output	Data stream (e.g., JSON, XML, binary data)	Comparison result (boolean, order, etc.)
Usage	Saving data, network transmission	Sorting, searching, identity comparison
Object modification	Object remains unchanged	Objects remain unchanged (unless otherwise implemented)
Order dependence	Property order may be important for deserialization	Order of objects in a collection matters for sorting