dupl
static sopno dupl(struct parse *p, sopno start, sopno finish);
copy = dupl(p, start+1, finish+1);
copy = dupl(p, start, finish);
copy = dupl(p, start, finish);
(void) dupl(p, p->pbegin[i]+1, p->pend[i]);
(void) dupl(p, p->pbegin[i]+1, p->pend[i]);