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[hgm]

EPDs have no 50-move or move-number fields. Only FENs have that...

[Dann Corbit]

EPDs have no 50-move or move-number fields. Only FENs have that...

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - fmvn 1; hmvc 0;
They have them, but they are decorated with a label.

[hgm]

Sure. But they are optional, and 0, 1 are their default values.

[chrisw]

EPDs have no 50-move or move-number fields. Only FENs have that...

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - fmvn 1; hmvc 0;
They have them, but they are decorated with a label.

I put that in as an issue to Python Chess about a week or so ago.

One more item: many online FEN strings come without the two final fields (moves since, movenum). the FEN reader complains. Might be useful if it added 0, 1, with some documentation explanation.

Response back: I need this quite frequently myself, but never got around to do it. Now implemented in 65e8729. Defaults to 0 1.

So, I think Python Chess now accepts both:
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq x, y

and appends an 0, 1 if x, y missing. It used to just issue an error, "fen strings have six fields"
I'm not sure what happens if fmvn is specifically used as an identifier.

[hgm]

I hate pedantic interfaces. WinBoard just uses a default value 0 for the ply counter if it is missing, and ignores the move number anyway, when it parses a FEN.

I guess stupid old NotePad would not even have a problem doing this; just do a 'Replace All' on " id " for " 0 1 id " if you insist on beraking the EPDs that way.

[niklasf]

So, I think Python Chess now accepts both:
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq x, y

Yeah, on the master branch it now even defaults to

Code: Select all

w - - 0 1

respectively. Not sure if that's a bit too relaxed ... in any case a user could parse, regenerate, compare to do strict validation.

I'm not sure what happens if fmvn is specifically used as an identifier.

This always worked as expected:

Code: Select all

>>> import chess
>>> board, ops = chess.Board.from_epd("rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - fmvn 2; hmvc 3;")
>>> board
Board('rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 3 2')
>>> ops
{'fmvn': 2, 'hmvc': 3}

However it will still reject

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id unquoted_string

because it attempts to parse this as a number or move.