Loss of Castling Rights

[andrew-buchanan]

Hi thanks for all your work.

Consider https://pdb.dieschwalbe.de/P0006972

Retractor thinks that it's ok for me to freeze wK, but not so. Black has made 4 pawn captures, which must include wKR which had to disrupt wK to escape.

Similarly https://pdb.dieschwalbe.de/P0003454

By the way, whenever I use Retractor successfully in PDB, in a proof of soundness or cookery, I record it: https://pdb.dieschwalbe.de/overview.jsp?expression=cpluscomment%3D%27retractor%27

So 35 so far: thank you!

All the best,
Andrew

[hwatheod]

In version 2.3, Retractor will detect that P0006972 is illegal if the white king is frozen.