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Swift Collections - Array
import Foundation
//CREATE
//declaration using type annotation syntax (arrays are strongly typed)
let stringArray : Array<String>
//initialiser syntax uses type inference mechanism
var intArray = Array<Int>()
let shorterIntArray = [Int]()
//array literals syntax - usually used to initialise with predefined list of values
let literalIntArray: [Int] = []
//immutable version of array
let immutableIPhones = ["11", "11 Pro", "11 Pro Max"]
//mutable array
var iPhones = ["11", "11 Pro", "11 Pro Max"]
//check elements
iPhones.count
iPhones.isEmpty
//MODIFY
//add elements
iPhones.append("XR")
iPhones.append(contentsOf: ["8", "8 Plus"])
//print(iPhones)
iPhones.insert("7", at: 0)
//print(iPhones)
//remove elements
//iPhones.removeFirst() //LIFO
//iPhones.removeLast() //FIFO
//iPhones.remove(at: 0)
//print(iPhones)
//UPDATE
//iPhones[0] = "5s"
//print(iPhones)
//SORT
//let sortedIPhones = iPhones.sorted() //elements that conform to the Comparable protocol
//print(sortedIPhones)
//COPY
//like all collection types in the standard library, arrays have value semantics - when you assign an existing array to another variable, the array content is copied.
var iPhonesCopy = iPhones
iPhonesCopy.removeLast()
print(iPhonesCopy)
print(iPhones)
//ACCESS ELEMENTS
//let firstIPhone = iPhones[0]
let firstIPhone = iPhones.first
let lastIPhone = iPhones.last
//ITERATE
//iterate over all elements
for iPhone in iPhones {
// print(iPhone)
}
//iterate over all elements and skip first
for iPhone in iPhones.dropFirst() {
// print(iPhone)
}
//iterate over all elements and skip last
for iPhone in iPhones.dropLast() {
// print(iPhone)
}
//iterate over all elements and get index of element
for (index, iPhone) in iPhones.enumerated() {
// print("\(index). \(iPhone)")
}
//FIND ELEMENT
//let firstNotNewIPhone = iPhones.firstIndex { (iPhone) -> Bool in
// return !iPhone.contains("11")
//}
//print(firstNotNewIPhone)
//TRANSFORM
let uppercasedIPhones = iPhones.map({ $0.uppercased() })
print(uppercasedIPhones)
let onlyNewIphones = iPhones.filter { (iPhone) -> Bool in
return iPhone.contains("11")
}
print(onlyNewIphones)
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