[Retros] Mushikui Reconstruction

Mu-Tsun Tsai tsai39 at illinois.edu
Fri May 20 11:57:08 EDT 2011

> The PGN spec is at http://www.chessclub.com/help/PGN-spec and says that

> "En passant captures do not have any special notation". So cxd6ep is

> written "cxd6" in PGN. This can be confirmed by playing a game with en

> passant in any chess program and saving the game as PGN.

Indeed, I read this part right after I posted the previous message.
Actually this is the only deviation between my format and the PGN spec.
I think this will makes thing a little better for the following two reasons:

1) If no "ep" is not used, then the distinction between an en passant
capture and a one-step pawn move followed by a capture can only be
distinguished when the position at that moment involves checks. This will
considerably reduce the possibility of composing problems regarding en
2) It seems to me that most people on PDB get used to add "ep" in their
comments, so stay this way might make things more "natural", so to speak.

P.S. Chessmaster output its PGN with "ep"... So not really "any chess
program" drop that "ep".

> Other things to look for: PGN specifies the use of # for checkmate (not

> ++), the use of "=" to denote promotion, the notations O-O and O-O-O for

> castling (not OO and OOO), and gives precise disambiguation rules when

> multiple pieces of the same type can move to the same square (e.g.

> Raxa3). All of these subtleties affect the number of stars.

The format I used agree with all these. Also double check is denoted by
simply "+", not "++".

I hope this clarifies the notation issue. Enjoy! :)

Mu-Tsun Tsai

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