Have you tried the link that Daniel posted? (You would have to scroll down beyond the debug output, which is still there because of the 'resign' problem.)
What the included code does is very similar to what you describe. If the moved piece is promotable it first looks up a (rank-dependent) array of choices in #choice (which might or might not include a Pawn, and would be 0 outside the zone), and then it does:
if #promo: // move already specifies promotion
if not #choice: // apparently outside the zone
die "You cannot promote on this move";
elseif not match #promo #choice: // or to a non-allowed piece
die "You cannot promote to such a piece";
endif;
elseif #choice and not $answered: // it should promote, but doesn't yet
askpromote #choice;
endif;
(#promo contains the promotion choice that was specified in the input move). If a choice was already specified, it is checked whether that choice is allowed. If not, and the promotion question was not already $answered (it could be if the user declined), and a choice is possible, it presents the choice through askpromote.
Note that the problem does NOT occur when you decline. It occurs when you choose to promote. (But only in games where there also is the option to decline.) When, in Daniel's link, I choose a white Pawn, it does play P g7-g8. But when I choose a white Zebra it dies, showing a game record that ends in:
39. Y g2-f7 39... k g8-f9 40. P g7-g8 40... ; Z-dest
So it has treated the Z-dest as a new move, for black! (Which my move parser of course doesn't recognize as a valid move.; hence the die.)
[Edit] I call this code from the Post-Game section, though. Could that make the difference? The same code does work without problems in the Mighty-Lion preset. And I recall having tested it too for cases that allow deferral.
Have you tried the link that Daniel posted? (You would have to scroll down beyond the debug output, which is still there because of the 'resign' problem.)
What the included code does is very similar to what you describe. If the moved piece is promotable it first looks up a (rank-dependent) array of choices in #choice (which might or might not include a Pawn, and would be 0 outside the zone), and then it does:
if #promo: // move already specifies promotion if not #choice: // apparently outside the zone die "You cannot promote on this move"; elseif not match #promo #choice: // or to a non-allowed piece die "You cannot promote to such a piece"; endif; elseif #choice and not $answered: // it should promote, but doesn't yet askpromote #choice; endif;(#promo contains the promotion choice that was specified in the input move). If a choice was already specified, it is checked whether that choice is allowed. If not, and the promotion question was not already $answered (it could be if the user declined), and a choice is possible, it presents the choice through askpromote.
Note that the problem does NOT occur when you decline. It occurs when you choose to promote. (But only in games where there also is the option to decline.) When, in Daniel's link, I choose a white Pawn, it does play P g7-g8. But when I choose a white Zebra it dies, showing a game record that ends in:
So it has treated the Z-dest as a new move, for black! (Which my move parser of course doesn't recognize as a valid move.; hence the die.)
[Edit] I call this code from the Post-Game section, though. Could that make the difference? The same code does work without problems in the Mighty-Lion preset. And I recall having tested it too for cases that allow deferral.