function exercise(Order memory order, uint256[] calldata floorAssetTokenIds) public payable {
    ..SNIP..
    // check position has not expired
    require(block.timestamp < positionExpirations[uint256(orderHash)], "Position has expired");
    ..SNIP..
}
function withdraw(Order memory order) public {
    ..SNIP..
    // check long position has either been exercised or is expired
    require(block.timestamp > positionExpirations[longPositionId] || isExercised, "Must be exercised or expired");
    ..SNIP..
}
function withdraw(Order memory order) public {
    ..SNIP..
    // check long position has either been exercised or is expired
    require(block.timestamp >= positionExpirations[longPositionId] || isExercised, "Must be exercised or expired");
    ..SNIP..
}
