Often, when we need a format or a template for date or time, we usually go for something like YYYY, MM, mm:ss, etc). Developing the static blog engine for this blog in Go, I’ve come across another approach – a use the real hardcoded values instead of the special symbols. For instance:

func format_time(t time.Time) string {
  return t.Format("2006.01.02-15.04.05")  // Similar to YYYY.MM.DD-hh.mm.ss
}

A full list of “magic” values (from time/format.go):

stdLongMonth      = "January"
stdMonth          = "Jan"
stdNumMonth       = "1"
stdZeroMonth      = "01"
stdLongWeekDay    = "Monday"
stdWeekDay        = "Mon"
stdDay            = "2"
stdUnderDay       = "_2"
stdZeroDay        = "02"
stdHour           = "15"
stdHour12         = "3"
stdZeroHour12     = "03"
stdMinute         = "4"
stdZeroMinute     = "04"
stdSecond         = "5"
stdZeroSecond     = "05"
stdLongYear       = "2006"
stdYear           = "06"
stdPM             = "PM"
stdpm             = "pm"
stdTZ             = "MST"
stdISO8601TZ      = "Z0700"  // prints Z for UTC
stdISO8601ColonTZ = "Z07:00" // prints Z for UTC
stdNumTZ          = "-0700"  // always numeric
stdNumShortTZ     = "-07"    // always numeric
stdNumColonTZ     = "-07:00" // always numeric

A few examples:

ANSIC       = "Mon Jan _2 15:04:05 2006"
UnixDate    = "Mon Jan _2 15:04:05 MST 2006"
RubyDate    = "Mon Jan 02 15:04:05 -0700 2006"
RFC822      = "02 Jan 06 15:04 MST"
RFC822Z     = "02 Jan 06 15:04 -0700" // RFC822 with numeric zone
RFC850      = "Monday, 02-Jan-06 15:04:05 MST"
RFC1123     = "Mon, 02 Jan 2006 15:04:05 MST"
RFC1123Z    = "Mon, 02 Jan 2006 15:04:05 -0700" // RFC1123 with numeric zone
RFC3339     = "2006-01-02T15:04:05Z07:00"
RFC3339Nano = "2006-01-02T15:04:05.999999999Z07:00"
Kitchen     = "3:04PM"
// Handy time stamps.
Stamp      = "Jan _2 15:04:05"
StampMilli = "Jan _2 15:04:05.000"
StampMicro = "Jan _2 15:04:05.000000"
StampNano  = "Jan _2 15:04:05.000000000"

I didn’t see such approach before, I’ve found it clearer and more logical.