SCM_CHARSET_ALNUM  803 src/char.c                 return Scm_GetStandardCharSet(SCM_CHARSET_ALNUM);
SCM_CHARSET_ALNUM  856 src/char.c             if (isalnum(code)) MASK_SET(CS(SCM_CHARSET_ALNUM), code);
SCM_CHARSET_ALNUM  917 src/gauche.h       SCM_CHARSET_ALNUM,