Re: missing possibility to use alternative translated month names in to_char function

ne 23. 8. 2026 v 8:32 odesílatel Bernd Reiß <bd_reiss(at)gmx(dot)at> napsal:

> Hi,
>
> On 23/08/2026 07:30, Pavel Stehule wrote:
> > Hi
> >
> > pá 21. 8. 2026 v 18:56 odesílatel Bernd Reiß <bd_reiss(at)gmx(dot)at> napsal:
> >
> > Hi Pavel,
> >
> > On 8/18/26 8:47 PM, Pavel Stehule wrote:
> > > Hi
> > >
> > > so 15. 8. 2026 v 14:03 odesílatel Bernd Reiß <bd_reiss(at)gmx(dot)at
> > <mailto:bd_reiss(at)gmx(dot)at>> napsal:
> > >
> > > Hi again,
> > >
> > > thanks for the updated patch.
> > > > TAMMON is not implemented, because glibc doesn't provide an
> > > > alternative form for abbreviated month names.
> > > > It is a question if it is better to raise an error, return
> > a non
> > > > alternative name or just ignore this flag. I have not strong
> > > > opinion about this. Inside DCH_to_char the prefix TM is
> > ignored when
> > > > it is not used. So I did the same.
> > > The Locale standard actually mentions abbreviated
> > alternative month
> > > names as
> > > "ab_alt_mon" (see [1]). I tested this by setting your
> > TAMMONTH strftime
> > > call to '%Ob'.
> > > If we set the locale to Russian and call the function for
> > May this
> > > actually returns
> > > an abbreviated version of the month name:
> > >
> > > Breakpoint 1, cache_locale_time () at pg_locale.c:772
> > > 772 if (strftime_l(bufptr, MAX_L10N_DATA, "%Ob",
> > timeinfo,
> > > locale) <= 0)
> > > (gdb) n
> > > 774 bufptr += MAX_L10N_DATA;
> > > (gdb) print bufptr
> > > $4 = 0x7ffde4554630 "май"
> > >
> > > Compared to the TMMON form of May in Russian this actually
> > makes a
> > > difference:
> > >
> > > postgres=# set lc_time='ru_RU.UTF8';
> > > SET
> > > postgres=# select to_char('2026-05-01'::date, 'TMMON');
> > > to_char
> > > ---------
> > > МАЯ
> > > (1 row)
> > >
> > > postgres=# select to_char('2026-05-01'::date, 'TAMMONTH');
> > > to_char
> > > ---------
> > > МАЙ
> > > (1 row)
> > >
> > > Again, TAMMONTH uses %Ob here. So I would argue for
> > implementing the
> > > abbreviated
> > > forms too.
> > >
> > >
> > > I implemented it - please check
> >
> > LGTM. I compiled it and it works as expected. I also like the
> > introduction of
> > the get_localized_*_months functions. However, this leads to
> > suffix_len being
> > declared and set but never used in the DCH_MONTH, DCH_Month, and
> > DCH_month
> > cases (as well as for the abbreviated equivalents) in
> > DCH_from_char. Passing
> > NULL and guarding in the functions would be an option to avoid
> > this. However,
> > I don't feel strongly about this.
> >
> > In DCH_to_char I think you forgot to refactor this if statement
> > for the
> > MON/Mon/mon cases?
> >
> > if (strlen(str) <= (n->key->len + TM_SUFFIX_LEN) *
> > DCH_MAX_ITEM_SIZ)
> > strcpy(s, str);
> >
> >
> > this code is removed in new version
> >
> >
> > >
> > > Please check updated patch
> > >
> >
> > With the if statements cleaned up this is a +1 for Ready for
> > Committer from me.
> >
> >
> > Regards
> >
> > Pavel
>
> Patch applies cleanly now on HEAD. New changes LGTM. Compiles without
> problems and
> regression tests are all green. I am moving this to Ready for Reviewer.
>

you are a reviewer :-)

Pavel

>
> Best
> Bernd
>