// Download Qq-rotations-90-degree.cql
// PGN output when run on sample.pgn

Q and q are on the same file or rank, separated
by a single square with a piece on it. The configuration
recurs in all 4 possible orientations. See Qq-rotations.cql for a more general version that considers 45 degree rotations as well

cql(input heijden.pgn variations)
 rotate90 4
    find shift {Qd4 [Aa]e4 qf4}