An html version of queencapturedelayed.cql.

Created by Gady Costeff and Lewis Stiller.

CQL 5.1
; Find positions in which White does not capture a non-pawn piece with the King ; in order to lose a tempo (part of the WCCT6 theme) ; This first finds a wtm position in the variation that is the same ; as a btm position in the mainline. It then checks that this position ; arises from the mainline when the White King has the choice to capture ; or not capture a Black non-pawn piece. ; The other option for the WCCT6 theme ; is for White to avoid a capture in order to ; gain (not lose) a tempo. This can be found similarly to the "rambling rook" theme cql(input heijden.pgn variations) variation wtm {relation mainline (tomove mismatch) (mismatch 0)} silent previous( not mainline+ {mainline wtm square $capture in [rbnq] move from K to $capture silent next(any mainline not K on $capture) comment "thematic non-capture" } )

CQL 3.2
;; This is an example of the full WCCT 6 theme. ;; It finds studies that contains a position ;; such that from that position White moves the King to an empty square rather than capturing a queen, which ;; the King instead captures on the next move. (match :pgn heijden.pgn :output wcct6.pgn (position :wtm :moveto . qb2 :attackcount a ab2 0 :attackcount K ab2 1 :sequence ((position :movefrom K) (position :attackcount a ab2 0) ) :shift :markall) )

After executing this with "> cql Wcct6.cql" there are 8 studies found in the Harold van der Heijden Database 2015.
NB. When you see {MATCH} in the text, it means that cql has found the position asked for.

Comments by Lewis Stiller about this theme:

- The existing CQL-3.2 wcct6.cql code looks for moves where a K  declines to capture a queen instead moving to an empty square.  

-  The comments say that the K (or white?) instead captures the queen on the next move.

-  The actual WCCT6 theme says that white avoids the capture of any non-pawn piece to "gain or lose a tempo",  

- see .  

- This was replaced by 5.1 code that looks for White to lose a tempo  and any piece captured, not just a queen, but captured by the King.


Below only 5 studies (selected by 3.2) are presented: