Golang and ISO 8601 ordinal dates

iso8601_ordinaldate.go

// This snippet demonstrates Golang formatting and parsing of
// ISO 8601 ordinal dates (4-digit year + "-" + ordinal day).
// Note: an ordinal day in this context is the nth day of
// the year, with Jan 1 being ordinal day 1 and Dec 31
// of non-leap year (a "common year") being day 365.

import (
	"time"
)

// FormatOrdinalDate returns an ISO 8601 ordinal date string.
// In this context, Ordinal date represents the nth day of the year.
func FormatOrdinalDate(date time.Time) string {
	return date.Format("2006-002")
}

// ParseOrdinalDate parses an ISO 8601 string representing a ordinal date,
// and returns the resultant golang time.Time insance.
func ParseOrdinalDate(isoOrdinalDate string) (time.Time, error) {
	return time.Parse("2006-002", isoOrdinalDate)
}