SwiftのArrayのCopy-on-Writeを確認してみる #CodePiece

CodePiece.swift

import Foundation

func address(_ o: UnsafeRawPointer) -> String {
    return String(
        format: "%p",
        Int(bitPattern: o)
    )
}

let array = [1,2,3]
address(array)   // "0x600000075ca0"

let array2 = array
address(array2)  // "0x600000075ca0"

let array3 = array.map { $0 }
address(array3)  // "0x600000077a20"