code: func Parse(expr string, randSeed uint64) (sched *Schedule, err error) {
  	toParse := ""
  	switch expr {
  	case "triggered":
  		return &Schedule{
  			asString:  "triggered",
  			randSeed:  randSeed,
  			triggered: true,
  		}, nil
  	case "continuously":
  		toParse = "with 0s interval"
  	default:
  		toParse = expr
  	}
  	if strings.HasPrefix(toParse, "with ") {
  		sched, err = parseWithSchedule(toParse, randSeed)
  	} else {
  		sched, err = parseCronSchedule(toParse, randSeed)
  	}
  	if sched != nil {
  		sched.asString = expr
  		sched.randSeed = randSeed
  	}
  	return sched, err
  }
docs: // Parse converts human readable definition of a schedule to *Schedule object.
  //
  // Supported kinds of schedules (illustrated by examples):
  //   - "* 0 * * * *": standard cron-like expression. Cron engine will attempt
  //     to start a job at specified moments in time (based on UTC clock). If when
  //     triggering a job, previous invocation is still running, an overrun will
  //     be recorded (and next attempt to start a job happens based on the
  //     schedule, not when the previous invocation finishes). This is absolute
  //     schedule (i.e. doesn't depend on job state).
  //   - "with 10s interval": runs invocations in a loop, waiting 10s after
  //     finishing invocation before starting a new one. This is relative
  //     schedule. Overruns are not possible.
  //   - "continuously" is alias for "with 0s interval", meaning the job will run
  //     in a loop without any pauses.
  //   - "triggered" schedule indicates that job is always started via a trigger.
  //     'Next' always returns DistantFuture constant.