xp                684 src/list.c         ScmExtendedPair *xp = SCM_NEW(ScmExtendedPair);
xp                685 src/list.c         xp->car = car;
xp                686 src/list.c         xp->cdr = cdr;
xp                687 src/list.c         xp->attributes = SCM_NIL;
xp                688 src/list.c         return SCM_OBJ(xp);