final ObjectMember nakedObjectMember = performContext.getObjectMember();
final OneToOneAssociation otoa = (OneToOneAssociation) nakedObjectMember;
// set
final PropertyClearFacet clearFacet = otoa.getFacet(PropertyClearFacet.class);
final CellBinding thatItBinding = performContext.getPeer().getThatItBinding();
if (clearFacet == null) {
throw ScenarioBoundValueException.current(thatItBinding, "(cannot clear)");
}
// validate setting to null
final Consent validConsent = otoa.isAssociationValid(onAdapter, null);
if (validConsent.isVetoed()) {
throw ScenarioBoundValueException.current(thatItBinding, validConsent.getReason());
}
clearFacet.clearProperty(onAdapter);
}