On Thu 12 Sep 2019 at 23:14:52 (-0400), The Wanderer wrote: > On 2019-09-12 at 21:49, David Wright wrote: > > On Thu 12 Sep 2019 at 12:42:01 (-0400), The Wanderer wrote: > >> On 2019-09-12 at 12:03, David Wright wrote: > > >>> It might be ambiguous if m were also an abbreviation for midnight, > >>> which I've never come across. > >> > >> Neither have I, but I also haven't come across any *other* abbreviation > >> for it which might be used in this type of context (have you?), and "M" > >> is just as intuitive a choice for abbreviating "midnight" as it is for > >> abbreviating "meridiem". > >> > >> One could argue "M" for "midnight" and "N" for "noon", but then you lose > >> the intuitiveness of M for meridiem, and people would mishear the two as > >> each other in nonline conversation all the time anyway. > > > > I don't see a need for a one-letter abbreviation for midnight, nor the > > wisdom in introducing one that's already used in the same context. > > Where would you use it? > > Wherever you need to specify midnight in a form where specifying any > other time would get the "AM"/"PM"/"M"(eridiem) abbreviation. > > To have a two-letter abbreviation for midnight but a one-letter one for > noon might be acceptable, although it would feel lopsided to me, but > just offhand I don't know of any suitable candidate to be that > two-letter abbreviation. Again, do you have any suggestions?
No: I'm the one suggesting it's neither desirable nor needed. So "Wherever you need to" doesn't help. > > Why not just drop 12-hour times? I don't think I've ever formatted a > > 12-hour time on a computer (unless you want to count the example > > quoted below). > > This isn't limited to the context of "on a computer". I think I > originally came up with the notion of referring to noon as "12:00 M" in > a context of mentioning the times in out-loud conversation; the > abbreviations are certainly used in more than just computerized contexts. > > For myself, I likely would drop 12-hour time. But as long as the world > isn't agreeing to do that, pursuing ways to make 12-hour time work more > logically and less ambiguously is still worthwhile. Oh, don't misunderstand me. I'm not arguing against using 12-hour time in ordinary conversation and in "real life". I've produced scores of tickets, posters and programmes with 12-hour times, and wouldn't dream of designing one that advertised a concert at 18:30 rather than 6.30 pm. I don't design posters with output generated by a date command, but if that became a necessity through sheer quantity, I would use date +'%l.%M %P', sure (but I'd add a test for 12). > And of course part of the reason I like the idea is because I find the > odd looks I get when I refer to "12:00 M" without previous explanation > to be amusing. > > >>> When I read emails, I only see the Date: line from the header, and > >>> the timedates used in the quotation lines. One thing I find odd is > >>> mixing AM/PM with hours containing a leading zero. I was always > >>> taught that 7 p.m. or 7pm was not written as 07, but I see that a > >>> lot here. Contrast > >>> > >>> $ TZ=Europe/Paris date +'%I.%M %p' > >>> 06.01 PM > >>> $ TZ=Europe/Paris date +'%l.%M %p' > >>> 6.01 PM > >>> $ > >> > >> That's probably to ease parsing by automated tools, such as sort, so > >> that they don't have to worry about handling field width. > > > > That wouldn't be possible anyway, because you don't have control over, > > for example, whether the time follows the date, and other variability. > > That just makes it even harder; not impossible, but unwieldy and > problematic enough that very few are likely to bother with trying. > > > No. I think it's more likely that most people don't notice > > conventions unless they're brought to their attention. Of course, if > > you're old enough, you had years of pre-digital experience when no > > one thought of padding dates and times with 0s. That might be why I > > notice 'odd' formatting like this. > > I may be confused. I thought we were talking about why some people / > tools use zero-padded hours fields with 12-hour time; I don't see how > the decision to do that could in any way arise from failure to notice a > convention without having it pointed out. I don't think they make a conscious *decision* to use leading zeroes, they just use the same old %I rather than %_I (≡ %l) because they hadn't thought about it, and their output didn't jar. Conventional: 8 pm 9 pm 10 pm 11 pm Casual: 08 pm 09 pm 10 pm 11 pm I've omitted the minutes so that the jarring effect might be more obvious. When reading fully specified times, with minutes and seconds, I think an experimental psychologist would be able to show that a leading zero fools the brain into parsing the time in 24-hour clock mode, and then the am/pm at the end causes reparsing, which slows comprehension. Perhaps it wouldn't work like that in America; I don't know. Cheers, David.
