/* Logic to determine whether or not a field is selectable */
#define Field_Is_Selectable(f) (((unsigned)((f)->opts) & O_SELECTABLE)==O_SELECTABLE)
#define Field_Is_Not_Selectable(f) (((unsigned)((f)->opts) & O_SELECTABLE)!=O_SELECTABLE)
/* Logic to determine whether or not a field is selectable */
#define Field_Is_Selectable(f) (((unsigned)((f)->opts) & O_SELECTABLE)==O_SELECTABLE)
#define Field_Is_Not_Selectable(f) (((unsigned)((f)->opts) & O_SELECTABLE)!=O_SELECTABLE)