* Kurtis Rader <kra...@skepticism.us> [210505 23:35]: > On Wed, May 5, 2021 at 8:23 PM Bagas Sanjaya <bagasdo...@gmail.com> wrote: > > > On 06/05/21 04.37, Ian Lance Taylor wrote: > > > You wrote 2009 where you need to write 2006. > > > > Wouldn't it possible to define arbitrary reference time and format it > > according to what it would like? > > > > If arbitrary literals for the various components were allowed it is certain > to create ambiguities. Especially, when you allow for locale specific > spellings and formatting of the date components.. The Go approach is easier > to understand if you read/speak English but suggests you can replace exact > literals (e.g., "2006") with what seems like an equivalent literal (e.g., > "2009") rather than the opaque POSIX `%Y`. This is the reason I am not a > fan of the Go approach compared to the POSIX strftime approach (see > https://pubs.opengroup.org/onlinepubs/009695399/functions/strftime.html)
The fact that this sort of confusion over the layout for Time.Format occurs frequently is a good indication that the approach taken is not as programmer-friendly as it ought to be. However, Time.Format has what I consider to be a much more egregious design flaw; one that should have ruled it out as the design for the standard library: the notation cannot unambiguously represent any desired format containing literals. If you want literal digits in the output, you are unlikely to be able use a single call to Time.Format without additional string manipulation afterward. Try to code the Go equivalent of the Linux command «date +"%Y 4 %d"». You either need two calls to Time.Format with string concatenation, or you must manipulate the string result of Time.Format to insert the literal "4". The %x notation is used in Go's fmt package, so this syntax must already be clearly understood by a Go programmer. This notation allows any literal to be unambiguously contained within the format string. Why add the cognitive overload of a completely different notation for time formatting that many programmers struggle to understand? Also, I would be very surprised if there were many Go programmers who never have to look up which reference digit to use for day and which for seconds; the order is arbitrary and not logical. It doesn't take much to remember that %H %M %S is hours, minutes, and seconds, while %y %m %d is year, month, and day. I would be willing to bet that if a Time.Printf were added to the time package, it would very quickly become the overwhelming favorite over Time.Format. This would be a compatible change that could easily be added without violating the Compatibility Promise. If I were designing this, however, I would not just copy the Linux date format. I would use format modifiers similar to the fmt package. E.g. instead of %y for two-digit year and %Y for four-digit year, year would always be %y with a way to indicate how it should be formatted. ...Marvin -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/20210506125722.uye4s7ls4na6rie4%40basil.wdw.
