ANCHOR_WORD_BOUND 1417 ext/mbstring/oniguruma/regcomp.c   case ANCHOR_WORD_BOUND:     r = add_opcode(reg, OP_WORD_BOUND);     break;
ANCHOR_WORD_BOUND 6168 ext/mbstring/oniguruma/regcomp.c     case ANCHOR_WORD_BOUND:      fputs("word bound",     f); break;
ANCHOR_WORD_BOUND 3243 ext/mbstring/oniguruma/regparse.c       tok->u.anchor = ANCHOR_WORD_BOUND;