Answers.Body: <p>Νικόλαος Μανωλακος asked:</p>
  
  <blockquote>
    <p>What would the SAN representation [<i>of a null move</i>] be?</p>
  </blockquote>
  
  <p>Several possibilities present themselves as to what the SAN notation can be, but <i>none</i> that I have found claim to be <i>the official</i> standard specification for SAN. The following results indicate within the quotation marks the annotation used (intended to be used without the quotation marks).
  <br><br><br></p>
  
  <p><b>NAG (Numeric Annotation Glyph) "$0"</b><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>IAW art. 10, table 1, line 1 [ref. 1, 2, 3]</i></p>
  
  <p><b>PGN's SAN: &nbsp;"--"</b><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>[ref. 4, 5, 6, 7]</i><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>Note: &nbsp;In ref. 7, null moves start out as mere comments, and can become [null] moves, but it's unclear as to whether they necessarily become so.</i></p>
  
  <p><b>PGN's SAN: &nbsp;"@@@@"</b><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>[ref. 8]</i></p>
  
  <p><b>"&lt;>", "--"</b><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>[ref. 9]</i><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>Note: &nbsp;"A Null Move acts as a placeholder for an expected move that is not played."</i></p>
  
  <p><b>"pass", "null", "@@@@"</b><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>[ref. 10]</i></p>
  
  <p><b>Stockfish's SAN: &nbsp;"null"</b><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>[ref. 11]</i></p>
  
  <p><b>"(null)"</b><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>[ref. 12]</i>
  <br><br></p>
  
  <hr>
  
  <p><br>
  <b>References:</b></p>
  
  <ol>
  <li><a href="http://www.saremba.de/chessgml/standards/pgn/pgn-complete.htm#c10" rel="nofollow">http://www.saremba.de/chessgml/standards/pgn/pgn-complete.htm#c10</a> </li>
  <li><a href="https://www.chessclub.com/user/help/PGN-spec" rel="nofollow">https://www.chessclub.com/user/help/PGN-spec</a> </li>
  <li><a href="https://metacpan.org/pod/distribution/Games-Chess/lib/Games/Chess/PGN.pod#NUMERIC-ANNOTATION-GLYPHS" rel="nofollow">https://metacpan.org/pod/distribution/Games-Chess/lib/Games/Chess/PGN.pod#NUMERIC-ANNOTATION-GLYPHS</a> </li>
  <li><a href="https://github.com/k2052/chess.rb/blob/master/lib/chess/san.rb" rel="nofollow">https://github.com/k2052/chess.rb/blob/master/lib/chess/san.rb</a> </li>
  <li><a href="https://www.cs.kent.ac.uk/people/staff/djb/pgn-extract/help.html#portability" rel="nofollow">https://www.cs.kent.ac.uk/people/staff/djb/pgn-extract/help.html#portability</a> </li>
  <li><a href="https://www.gnu.org/software/xboard/whats_new/4.6.0/#tag-D6" rel="nofollow">https://www.gnu.org/software/xboard/whats_new/4.6.0/#tag-D6</a> </li>
  <li><a href="http://www.triplehappy.com/faq.html" rel="nofollow">http://www.triplehappy.com/faq.html</a> </li>
  <li><a href="https://www.gnu.org/software/xboard/engine-intf.html#8" rel="nofollow">https://www.gnu.org/software/xboard/engine-intf.html#8</a> </li>
  <li><a href="http://www.enpassant.dk/chess/palview/manual/pgn.htm#pgncontnull" rel="nofollow">http://www.enpassant.dk/chess/palview/manual/pgn.htm#pgncontnull</a> </li>
  <li><a href="http://hgm.nubati.net/alien.html" rel="nofollow">http://hgm.nubati.net/alien.html</a> </li>
  <li><a href="https://github.com/mcostalba/FishCooking/blob/master/src/notation.cpp" rel="nofollow">https://github.com/mcostalba/FishCooking/blob/master/src/notation.cpp</a> </li>
  <li><a href="https://github.com/erashid/DON/blob/master/src/Notation.cpp" rel="nofollow">https://github.com/erashid/DON/blob/master/src/Notation.cpp</a> </li>
  </ol>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-06-27T23:39:36.273Z
Answers.LastActivityDate: 2016-06-27T23:39:36.273Z
Answers.UserDisplayName: Charles Rockafellor
Body: <p>The long algebraic notation (lan) for null move is usually 00-00 or simply 0000. Chess engines that support the nullmove: "give up a turn, and let the other side move" typically use this as its part of UCI. What  would the SAN representation be? </p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-04-02T23:16:25.607Z
Comments.Text: Actually, I'm not even aware there is such thing as nullmove in SAN. But I could be wrong.
Comments.UserDisplayName: SmallChess
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-04-03T00:41:50.533Z
Comments.Text: I'm guessing 00 similar to pawn move d4
Comments.UserDisplayName: Νικόλαος Μανωλακος
Tags: <engines><notation><uci>
Title: SAN for nullmove?
ThreadText: # SAN for nullmove?
  
  (Asked by: username_0 on 2016-04-02)
  
  The long algebraic notation (lan) for null move is usually 00-00 or simply 0000. Chess engines that support the nullmove: "give up a turn, and let the other side move" typically use this as its part of UCI. What would the SAN representation be?
  
  **Tags:** engines, notation, uci
  
  > **Comments:**
  > **username_1**: Actually, I'm not even aware there is such thing as nullmove in SAN. But I could be wrong.  
  > **username_0**: I'm guessing 00 similar to pawn move d4  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_2 on 2016-06-27. Score: 3
  
  username_0 asked:
  
  > What would the SAN representation [*of a null move*] be?
  
  Several possibilities present themselves as to what the SAN notation can be, but *none* that I have found claim to be *the official* standard specification for SAN. The following results indicate within the quotation marks the annotation used (intended to be used without the quotation marks).
  
  **NAG (Numeric Annotation Glyph) "$0"**  
       *IAW art. 10, table 1, line 1 [ref. 1, 2, 3]*
  
  **PGN's SAN:  "--"**  
       *[ref. 4, 5, 6, 7]*  
       *Note:  In ref. 7, null moves start out as mere comments, and can become [null] moves, but it's unclear as to whether they necessarily become so.*
  
  **PGN's SAN:  "@@@@"**  
       *[ref. 8]*
  
  **"<>", "--"**  
       *[ref. 9]*  
       *Note:  "A Null Move acts as a placeholder for an expected move that is not played."*
  
  **"pass", "null", "@@@@"**  
       *[ref. 10]*
  
  **Stockfish's SAN:  "null"**  
       *[ref. 11]*
  
  **"(null)"**  
       *[ref. 12]*
  
  ---
  
  **References:**
  
  1. <http://www.saremba.de/chessgml/standards/pgn/pgn-complete.htm#c10>
  2. <https://www.chessclub.com/user/help/PGN-spec>
  3. <https://metacpan.org/pod/distribution/Games-Chess/lib/Games/Chess/PGN.pod#NUMERIC-ANNOTATION-GLYPHS>
  4. <https://github.com/k2052/chess.rb/blob/master/lib/chess/san.rb>
  5. <https://www.cs.kent.ac.uk/people/staff/djb/pgn-extract/help.html#portability>
  6. <https://www.gnu.org/software/xboard/whats_new/4.6.0/#tag-D6>
  7. <http://www.triplehappy.com/faq.html>
  8. <https://www.gnu.org/software/xboard/engine-intf.html#8>
  9. <http://www.enpassant.dk/chess/palview/manual/pgn.htm#pgncontnull>
  10. <http://hgm.nubati.net/alien.html>
  11. <https://github.com/mcostalba/FishCooking/blob/master/src/notation.cpp>
  12. <https://github.com/erashid/DON/blob/master/src/Notation.cpp>
  
  
  ---
  
  