enpassantrelation.cql

; enpassantrelation.cql can be downloaded here.

; Find games where there are two identical positions except that
; enpassant is legal in one, but not legal in the other.
  

cql(input heijden.pgn variations )
flipcolor
   wtm
   move enpassant
   relation wtm 
     not move previous
              from pa-h7
              to horizontal 1 Pa-h5
     (mismatch 0)