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Implement C's Switch in Python 3


On Sun, Feb 3, 2019 at 1:35 PM DL Neil <PythonList at danceswithmice.info>
wrote:

> On 3/02/19 10:16 PM, Chris Angelico wrote:
> > On Sun, Feb 3, 2019 at 8:09 PM DL Neil <PythonList at danceswithmice.info>
> wrote:
> >> On 3/02/19 9:45 PM, Chris Angelico wrote:
> >>> Which is why I always write dates in sorted format, usually eschewing
> >>> delimiters:
> >>> //CJA 20160511: Is this still happening? I don't remember seeing it in
> >>> three parts of forever.
> >> Sure is. It is an acceptable alternative under the ISO standard.
> >
> > Not sure if you're responding to the content of the comment there;
>
> Comment? I don't see no #, ''', or """!
> (am teasing)
>
>
> [ccyymmdd cf ccyy-mm-dd]
> >> Some would say it is more sensible to use when storing data because it
> >> removes the dash/hyphen separators in exchange for implying the
> >> fixed-format. (more bytes/characters saved if extend to include the
> time)
> >>
> >> I'm not going there - recalling folk from these memory-is-cheap times
> >> being less able to understand why we used to save 'expensive' storage
> >> space by using yy-years (instead of ccyy) and thus 'causing' "the
> >> millennium bug" aka Y2K!
> >
> > Skipping the delimiter isn't about saving space, it's about
> > consistency. If I say "non-delimited sorted date", you can almost
> > certainly write out a character-for-character identical date - handy
> > if you want to search a bunch of files, for instance. Having
> > delimiters leaves people free to dispute whether they should be
> > slashes, hyphens, dots, or maybe something else.
>
> This logic indisputable.
>
> However, the whole purpose of an ISO standard is to remove "dispute",
> locally and internationally! Thus, if not sufficiently-well stated
> earlier, the standard is actually for information interchange purposes.
>
>
>  >> I find it much slower to decode than reading the same with embedded
>  >> separators!
>  > Sure. I mainly use it in contexts where the most important information
>  > is simply "that's a date", rather than actually caring what the date
>  > *is*.
> [paras re-ordered]
>
> +1
>
>
> In case other readers are following-along-at-home, and the (above)
> purpose of the standard was insufficiently obvious, I did a bit of
> review 'homework':
>
> - ISO standards are still not $free
>
> - a good write-up from the ISO appears on the Wayback machine at
>
> https://web.archive.org/web/20110614235056/http://www.iso.org/iso/support/faqs/faqs_widely_used_standards/widely_used_standards_other/date_and_time_format.htm
> - the above makes the point about "interchange" and offers similar
> examples of date-confusion to those 'here'/earlier
> - mention is made of formats including/excluding delimiters
> (I haven't been able to check this, but can't find any evidence that
> separators other than "-" are allowed (in dates) )
>
> - in lieu of the ISO text, those of us working over the Internet will
> turn to RFC 3339
> - this is a slight simplification of the ISO standard
> - the ABNF appendix *requires* a dash/hyphen as (date) separator
>
> - Markus Kuhn at Cambridge (British university) provides a readable and
> thought-provoking summary at https://www.cl.cam.ac.uk/~mgk25/iso-time.html
> - uses dashes/hyphens
> - discusses international considerations (I've just learned that the
> Chinese date notation preceded the ISO order, as did the conventions of
> a number of other countries)
> - supports the compact/'no debate' format "The hyphens can be omitted if
> compactness of the representation is more important than human
> readability" (as well as caring for my fading vision)
>
>
> >> I wouldn't use it in a 'visible' situation though, eg a fileNM. Yes, it
> >> is shorter, but as my eyes age (they are already older than my teeth!),
> > Guess your teeth better work on catching up...
>
> Can't put them under the pressure of thinking it is a race - they could
> decide to drop out!
>
>
> >>> That said, I am aware that I am not in any way a "normal person".
> >>> Using month names as per your other example is probably a fair
> >>> compromise with other humans.
>
> In this life, one does have to make allowances...
>
>
> >> There's normal and there's normal - like it's tomato or tomato?
> > I dunno. I'm the kind of normal that likes tomatoes (not to be
> > confused with tomatoes). Does that help?
>
> If you like tomatoes, and tomatoes are fruit, do you (normally) chug
> tomato sauce (ketchup) as if it is fruit juice?
>

I'm surprised that no one has yet addressed the year 10000 problem.
Hopefully we're doing numeric, not alpha sorts on the stuff before the 1st
'-'. And, the compact versions will really screw up :).
-- 

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