exampleRefactorTimeAspect.js

function timeAspect(joinPoint, logger) {
    const aspect = {
      logger,
      timer: {
        start: function () { this.startTime = Date.now() },
        stop: function () { this.stopTime = Date.now() },
        time: function () { return this.stopTime - this.startTime }
      },
      before: function () { this.timer.start() },
      after: function () { this.timer.stop(), this.logger.log(timer.time) }
    }; 
    return decorate(joinPoint, aspect)
}