[Q] Support Roman month numbers, #'format-time-string

[Stephen J. Turnbull]

QUERY

Aidan Kehoe writes:

 > This change would be more useful in the C library, but I don’t have
 > commit access there.

 > + at item %\xe6 (the ISO-8859-1 lowercase ae character)
 > +This stands for the month as a lowercase Roman number (i-xii)
 > + at item %\xc6 (the ISO-8859-1 uppercase AE character)
 > +This stands for the month as an uppercase Roman number (I-XII)

This is not necessarily true in non-Mule because of the unibyte font
hack.  What do you think about adding a note?  Something like:

    In non-Mule (unibyte) XEmacs, \xe6 and \xc6 will be converted
    into literal byte values, and how they appear will depend on the
    registry of the font being used.

 > diff -r b6a398dbb403 -r 1537701f08a1 src/editfns.c
 > --- a/src/editfns.c	Wed Sep 01 12:51:32 2010 +0100
 > +++ b/src/editfns.c	Thu Sep 02 12:00:06 2010 +0100
 > @@ -1044,11 +1044,10 @@
 >  %Y is replaced by the year with century.  %z is replaced by the
 >  time zone as a numeric offset (e.g +0530, -0800 etc.)  %Z is
 >  replaced by the time zone abbreviation.
 > +%\xe6 is replaced by the month as a lowercase Roman number (i-xii)
 > +%\xc6 is replaced by the month as an uppercase Roman number (I-XII)

Does this actually work correctly?  I worry a little about this
inaccuracy (what the user sees in non-Mule with a font other than ISO
8859-1 is not going to work on Mule or default non-Mule).