ccs               895 src/regexp.c               ScmObj ccs = Scm_CopyCharSet(SCM_CHARSET(y));
ccs               896 src/regexp.c               ccs = Scm_CharSetComplement(SCM_CHARSET(ccs));
ccs               897 src/regexp.c               return Scm_CharSetLE(SCM_CHARSET(x), SCM_CHARSET(ccs));