PGN standard for comments

[adams161]

Hi, a user sent me this game:

[Event "?"]
[Site "?"]
[Date "2019.04.09"]
[Round "?"]
[White "Player"]
[Black "Player"]
[Result "*"]

1. d4 Nf6 2. c4 d5 3. Nf3 dxc4 (3... e6 4. Nc3 Be7 5. Bg5) 4. g3 c5 5. dxc5 *

Now openingtree cant read that as the comments are ( ) not { }. But i noticed Fritz 13 can. What is done here? Am i correct this is not supported or is it some expected short hand?

[kranium]

Hi, a user sent me this game:

[Event "?"]
[Site "?"]
[Date "2019.04.09"]
[Round "?"]
[White "Player"]
[Black "Player"]
[Result "*"]

1. d4 Nf6 2. c4 d5 3. Nf3 dxc4 (3... e6 4. Nc3 Be7 5. Bg5) 4. g3 c5 5. dxc5 *

Now openingtree cant read that as the comments are ( ) not { }. But i noticed Fritz 13 can. What is done here? Am i correct this is not supported or is it some expected short hand?

Hi Mike,

as far as I am aware,
comments are {}
variations are ()

http://www.saremba.de/chessgml/standard ... htm#c8.2.5

[adams161]

i updated openingtree to skip stuff between ( ). we dont have variation support but now they wont break us. I had not realized that the variations were not just part of comments as i often saw them there.

[hgm]

Some GUIs put variations (notably annotation with PVs from an engine analysis) in the PGN as plain {} comments. This is allowed, of course, but I have always argued it is a mistake. Because it makes it impossible for GUIs that do support the PGN standard for recursive variation to show them, and allow you to play through them.

Note that, unlike plain comments, variations can be nested, and the parentheses will have to be balanced. Comments will end at the first }, no matter how many {{{ there were before them. This is not entirely trivial, as unbalanced parentheses might occur in comments. E.g. after

( .... ( ... { good move : - ) }

you are stil two ) short for being back in the main line, not one!

[adams161]

looks like i'm missing that variants can be nested. i suppose now a nested file would break. Well will get to it. comments wont be a problem wtih my code as we end them on first }.