Date: Tue, 29 Apr 1997 06:24:35 -0400
From: Robert Jasiek <jasiek@berlin.snafu.de>
Subject: Re: RE and Date formats

>   - for more than two days:
>     just specify the first and the last day the game was played and use
>     ':' as delimeter, e.g. [1997-02-10:03-12]
>     Year/month may be omitted for end date if they equal the beginning
>     date

This is not enough. Then st like
[1997-02-10:03-12,15] or alternatively
[1997-02-10:03-12][1997-03-15]
seems to become illegal. Besides you have to specify operator
association.

>   - maybe we could even specify a sohisticated format like the one
>     Robert mentioned, i.e. combination of ',' and ':' within the
>     simpletext value.
>     But this might be a little bit too much of a good thing.

As you see from the above example a combination or a list of [] or
a separation list is necessary. I agree that a combination of two 
operators is too complicated.
The most difficult possibilty is to allow a list of [] with
date
date,postdate
Adate:Bdate

being valid expressions in a simpletext.

> I think that the first date is the most important (beginning of game).

This is true for sorting. But in many title games on the first day only
some celebratial moves are played, while the main part can be played on
several days some months later. I think, the user wants to get all these
days in correct format, i.e. they must also be in ISO.

> If this is in ISO format I don't care about the rest, i.e.
> it might be bad style, but I would've no problem with:
> DT[1997-04-26 16pm-22pm, rainy afternoon]

It is better to separate the ISO dates from each other and to separate
the rest simpletext by the same separator: Example with separator '#' :
[date#date#restsimpletextabout sunshine]

---------------------------------------------------------
What to do: 1 = new format , or 2 = expanded old format :
---------------------------------------------------------

Possibility 1:
-----------------

With - as David says - only 5-10% of old dates being correct we may as
well choose a new format without doing us much harm:

list of [simpletext] 
, where simpletext is interpreted as ISO-date or blablasimpletext.

Examples:

;DT[1997-04-28]
;DT[played on a warmy 4th April in year 3 of Meiji]
;DT[1996-12-31][1997-01-01][1997-01-02][1997-04-28]
[dayly schedule 10am-4pm]

Note: wrong old dates are displayed as blablasimpletext.

Compression could be added but is not really necessary for dates:
Adate:Bdate like ;DT[1996-12-31:1997-01-02] .

Possibility 2:
-----------------

Maintains old format (if with comma) 
and allows several dates and comments and 
treats wrong old dates as blablasimpletext.

[simpletext]

where ',' serves as a seperator and each separated part may be
of one of the following formats:

yyyy-mm-dd
yyyy-mm
yyyy
mm-dd
mm
dd
blablasimpletext

Interpretation:
>From left to right.
Left-most must contain yyyy or all will be treated as blablasimpletext.
mm-dd or mm acquires the last preceding yyyy.
If dd is preceded by some mm and some yyyy (possibly at some other
place), it acquires the last preceding mm and the last preceding
yyyy.
If xx follows yyyy-mm-dd or mm-dd or dd, then xx is dd.
If xx follows yyyy-mm or mm, then xx is mm.
All other will be treated as blablasimpletext.

Compression is not allowed.

As you see the new format is much simpler.

> 
> I'm still not sure what to do about illegal date/result fields.
> /Arno

See above: treat as blablasimpletext.

Do you prefer possibility 1 or 2?

--robert