SCM_CLASS_READ_REFERENCE 3038 src/class.c        BINIT(SCM_CLASS_READ_REFERENCE,   "<read-reference>", NULL);
SCM_CLASS_READ_REFERENCE 1639 src/gauche.h   #define SCM_READ_REFERENCE_P(obj) SCM_XTYPEP(obj, SCM_CLASS_READ_REFERENCE)
SCM_CLASS_READ_REFERENCE  225 src/read.c         SCM_SET_CLASS(a, SCM_CLASS_READ_REFERENCE);