ONIG_OPTION_NEGATE_SINGLELINE  412 include/ruby/oniguruma.h #define ONIG_OPTION_DONT_CAPTURE_GROUP   (ONIG_OPTION_NEGATE_SINGLELINE  << 1)
ONIG_OPTION_NEGATE_SINGLELINE 5937 regcomp.c        if ((option & ONIG_OPTION_NEGATE_SINGLELINE) != 0) {