dateutil

var (
	// EveryMinute will chop up a timespan into 60s intervals;
	// https://english.stackexchange.com/questions/3091/weekly-daily-hourly-minutely.
	EveryMinute = makeIntervalFunc(
		func(t time.Time) time.Time { return now.With(t).BeginningOfMinute() },
		func(t time.Time) time.Time { return now.With(t).EndOfMinute() },
	)
	// Hourly will chop up a timespan into 60min intervals.
	Hourly = makeIntervalFunc(
		func(t time.Time) time.Time { return now.With(t).BeginningOfHour() },
		func(t time.Time) time.Time { return now.With(t).EndOfHour() },
	)
	// Daily will chop up a timespan into 24h intervals.
	Daily = makeIntervalFunc(
		func(t time.Time) time.Time { return now.With(t).BeginningOfDay() },
		func(t time.Time) time.Time { return now.With(t).EndOfDay() },
	)
	// Weekly will chop up a timespan into 7 day intervals.
	Weekly = makeIntervalFunc(
		func(t time.Time) time.Time { return now.With(t).BeginningOfWeek() },
		func(t time.Time) time.Time { return now.With(t).EndOfWeek() },
	)
	// Monthly will chop up a timespan into monthly intervals.
	Monthly = makeIntervalFunc(
		func(t time.Time) time.Time { return now.With(t).BeginningOfMonth() },
		func(t time.Time) time.Time { return now.With(t).EndOfMonth() },
	)
)