A simple way to time code using Swift.

CodeTimer.swift

import Foundation

class CodeTimer {
    var startTime: CFAbsoluteTime = 0
    init() { start() }

    func start() { startTime = CFAbsoluteTimeGetCurrent() }

    func log(_ message: String) {
        let timeElapsed = CFAbsoluteTimeGetCurrent() - startTime
        let s = String(format: "%.3f", timeElapsed)
        print("\(message) \(s) second(s).")
    }
}

Example usage:

    let timer = CodeTimer()
    timer.log("Time elapsed:") // Time elapsed: 0.380 second(s).