*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
} else {
//elem is not null, so we carry on
if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
//Look at enabled_element_set, and jump to disabled_element_set when finished
*elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);
*elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
} else {
//elem is not null, so we carry on
if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
//Look at enabled_element_set, and jump to disabled_element_set when finished
*elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);