Date: Tue, 25 Mar 1997 12:35:07 -0500
From: David Fotland <fotland@hpihoah.cup.hp.com>
Subject: SGF compatibility questions


I'm putting the finishing touches on my SGF support in Many Faces, and
I have some questions...

First, I'd like to be able to read sgf files that contain mail headers.
This is easy in Ishi Format since everything before the 'EVENT' is
specified to be ignored.

For SGF I tried skipping to the initial "(;", but I found that there
are some sgf files that don't have a ';' before the root node.  Is this
allowed?  I have quite a few of them from Van Der Steen's web site.

What does smart game board do with these files?  Now, I detect and correct
them, but it prevents me from reading sgf files with mail headers.


Second, when was the FF keyword introduced?  Was it part of FF[2] or FF[3]?

Third, the triples for describing the position are confusing.  For example
DM (even position) is mentioned in FF[4], but is not in Martin's spec
for FF[3].  Is this really new in FF[4]?  BM (bad move) seems to be dropped
from FF[4].  Altogether, I count 9 different triples that I could see
in files (DM, UC, GB, GW, BM, CH, TE, DO, IT), and from my readings of
the various specs, only 2 of them (GB and GW) exist in all versions of
the spec.  Does anyone have any recommendation for which ones MFGO should
support?  I'm tempted to read them all, convert them to commentary text,
and not allow the user to edit them.  I would not generate them into an
output file.

Do people find these generally useful?  I'd guess not since the definition
changes so often.  Is it legal to have several of these in the same node?
Martin's spec implies yes, but FF[4] says no.  Has anyone seen files
with multiple triples in the same node?

Fourth, I have some files with a move in the root node.  I think of a move
as the move that leads to this node.  So the root node shouldn't have
a move in it.  Currently I correct this by adding a new node.  What do
other programs do?  

Does anyone else know of popular, odd behavior, or strange files?  It seems
that as I test, every few files I look at, I find some other strange,
unexpected thing.

Thanks,

David Fotland