SCM_WRITE_CASE_NOFOLD 1589 src/gauche.h       SCM_WRITE_CASE_NOFOLD = 8,  /* case-sensitive mode.  no need to escape
SCM_WRITE_CASE_NOFOLD  115 src/write.c        SCM_WRITE_CASE_FOLD:SCM_WRITE_CASE_NOFOLD)