MoussaHellal

class Human {
    
    static var name = "Mousa"
    
    class var age : Int {
        return 27
    }
}
// Type Method : we accessed both properties without even creating an instance of Human Class.
print(Human.name)

MoussaHellal

class Human {
    
    static var name = "Mousa"
    
    class var age : Int {
        return 27
    }
}
// Type Method : we accessed both properties without even creating an instance of Human Class.
print(Human.name)

MoussaHellal

extension Date {
    func toDateString() -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "yyyy-MM-dd"
        return dateFormatter.string(from: self)
    }
    
    func toTimeString() -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "HH:mm:ss"

MoussaHellal

extension Double {
    func rounded(toPlaces places:Int) -> Double {
        let divisor = pow(10.0, Double(places))
        return (self * divisor).rounded() / divisor
    }
}

let number = 34.33356
print(number.rounded(toPlaces: 3))

MoussaHellal

extension Sequence {
    func group<GroupingType: Hashable>(by key: (Iterator.Element) -> GroupingType) -> [[Iterator.Element]] {
        var groups: [GroupingType: [Iterator.Element]] = [:]
        var groupsOrder: [GroupingType] = []
        forEach { element in
            let key = key(element)
            if case nil = groups[key]?.append(element) {
                groups[key] = [element]
                groupsOrder.append(key)
            }

MoussaHellal

extension Array {
    var shuffled: Array {
        var elements = self
        return elements.shuffle()
    }
    @discardableResult
    mutating func shuffle() -> Array {
        let count = self.count
        indices.lazy.dropLast().forEach {
            swapAt($0, Int(arc4random_uniform(UInt32(count - $0))) + $0)

MoussaHellal

extension String {
    func toDouble() -> Double? {
        return NumberFormatter().number(from: self)?.doubleValue
    }
}

let number = "34.4"
print(number.toDouble())

MoussaHellal

extension String {
    func strikeThrough() -> NSAttributedString {
        let attributeString =  NSMutableAttributedString(string: self)
        attributeString.addAttribute(NSAttributedString.Key.strikethroughStyle, value: NSUnderlineStyle.single.rawValue, range: NSMakeRange(0,attributeString.length))
        return attributeString
    }
}

// Usage
let hello = "Hello World".strikeThrough()

MoussaHellal

let firstSetOfNumbers: Set = [7, 5, 10, 6, 12]
let secondSetOfNumbers: Set = [5, 7, 9, 11, 13]

firstSetOfNumbers.sorted() // returns an ordered Set by value
// Output: [5, 6, 7, 10, 12]
firstSetOfNumbers.intersection(secondSetOfNumbers).sorted() // returns an intersected sorted set between two sets
// Output: [5, 7]
firstSetOfNumbers.subtracting(secondSetOfNumbers).sorted() // returns result of subtracted set from another set
// Output: [6, 10, 12]
secondSetOfNumbers.union(firstSetOfNumbers).sorted()

MoussaHellal

setOfNumbers.contains(8)     // to check if set contains a specific value.