setbvalue
setbvalue(L->top, (b != 0)); /* ensure that true is 1 */
setbvalue(&o, b);
setbvalue(&v, 1); /* boolean 'true' to be the value of all indices */
setbvalue(o, 1); /* t[string] = true */
setbvalue(o,LoadChar(S));
setbvalue(ra, GETARG_B(i));
setbvalue(ra, res);