Re: [Pharo-dev] [squeak-dev] Time now print24

[stepharo]

I like the idea of Go to have a separate date-printer.


Stef


Le 8/7/16 à 11:23, Sven Van Caekenberghe a écrit :

On 08 Jul 2016, at 10:49, Tobias Pape <das.li...@gmx.de> wrote:


On 07.07.2016, at 18:33, Eliot Miranda <eliot.mira...@gmail.com> wrote:

Hi All,

    how does one produce a nice timestamp, simply date and time as in

    7/7/2016 09:19:38

What's with 'TimeStamp now'  (prints  '8 July 2016 10:34:36 am')

or this one:

TimeStamp now in: [:t |
        String streamContents: [:s |
                t asDate printOn: s format: #(2 1 3 $/ 1 1 2).
                s space.
                t asTime print24: true showSeconds: true on: s]]

Too bad TimeStamp is deprecated in Pharo4, so this works in pharo:

Yes, it is gone. It was a subclass whose only feature was a different print 
representation. It was also confusing, why choose it or DateAndTime.

We folded TimeStamp's functionality into DateAndTime (see 
#printSeparateDateAndTimeOn: and #readSeparateDateAndTimeFrom:)

DateAndTime now rounded in: [:t |
        String streamContents: [:s |
                t asDate printOn: s format: #(2 1 3 $/ 1 1 2).
                s space.
                t asTime print24: true showSeconds: true on: s]]

But DateAndTime knows no #rounded in Squeak, buuut:

=======================

This works for both:


DateAndTime now in: [:t |
        String streamContents: [:s |
                t asDate printOn: s format: #(2 1 3 $/ 1 1 2).
                s space.
                t printHMSOn: s]]

=====

Best regards
        -Tobias

PS: I'd prefer ISO, nonetheless: https://xkcd.com/1179/

Yes, that was my point exactly. Thanks for the cool link!

In the same line, the AM/PM don't make sense, and the timezone (or Z) is 
required.

https://en.wikipedia.org/wiki/ISO_8601

Something like 2016-07-08 08:41:52 Z or 2016-07-08 08:41:52 +00:00 is perfectly 
readable.

BTW, these are unambigiously parseable as well (for example, using ZTimestamp).

ZTimestamp readFromString: '2016-07-08 08:41:52 Z'.

"2016-07-08T08:41:52Z"

ZTimestamp readFromString: '2016-07-08 08:41:52 +00:00'.

"2016-07-08T08:41:52Z"

Using ZTimestampFormat, which is an example based formatter/parser, like Go's, 
you can easily produce this slightly more human friendly format.

(ZTimestampFormat fromString: '2001-02-03 16:05:06 +00:00') format: DateAndTime 
now.

"'2016-07-08 11:16:54 +02:00'"

And the reverse (obviously you share/predefine/cache the specific format 
object).

(ZTimestampFormat fromString: '2001-02-03 16:05:06 +00:00') createDateAndTime; 
parse: '2016-07-08 11:16:54 +02:00'.

"2016-07-08T11:16:54+02:00"

        (or the German way: 25.12.2015 :P)

Trivial, right?

So

    Date today mmddyyyy, ' ', Time now print24 '7/7/2016 09:22:40.914'

.914, ah, nanos.  How useful.  Let's get rid of them.  No nanos: accessor so

    Date today mmddyyyy, ' ', (Time now nanos: 0) print24 => MNU

but there's a seconds accessor, so

    Date today mmddyyyy, ' ', (Time now seconds: Time now seconds; print24) 
'7/7/2016 00:00:41

??  So seconds: is private, and isn't the dual of Time seconds:

Time seconds
        ^ self second
Time second
        ^ self asDuration seconds
Duration seconds
        "Answer the number of seconds the receiver represents."
        ^seconds rem: SecondsInMinute

Looks broken to me.

Personally I think print24 should not print sub seconds.

cc'ing to Pharo because I want this timestamp to be the same in both dialects 
for a profiling tool we want to use in both dialects.
_,,,^..^,,,_
best, Eliot