lmdbscan: better ability to handle duplicates in a special way about lmdb-go HOT 3 CLOSED

    err := env.View(func(txn *lmdb.Txn) (err error) {
        scanner := lmdbscan.New(txn, dbi)
        defer scanner.Close()

        for scanner.SetNext(nil, nil, lmdb.NextNoDup, lmdb.NextDup)  {
            var vals [][]byte
            k := scanner.Key()
            for scanner.Scan() {
                vals = append(vals, scanner.Val())
            }
            log.Printf("k=%q vals=%q", k, vals)

            // this may even be optional
            if scanner.Err() != nil {
                return scanner.Err()
            }
        }
        return scanner.Err()
    })
    if err != nil {
        panic(err)
    }

    err := env.View(func(txn *lmdb.Txn) (err error) {
        scanner := lmdbscan.New(txn, dbi)
        defer scanner.Close()

        for scanner.Set(nil, nil, lmdb.NextNoDup) {
            var vals [][]byte
            k := scanner.Key()
            dup0 := scanner.Val()
            if scanner.SetNext(nil, nil, lmdb.GetMultiple, lmdb.NextMultiple) {
                vals = [][]byte{dup0}
            }
            for scanner.Scan() {
                multi := lmdb.WrapMulti(scanner.Val(), len(dup0))
                vals = append(vals, multi.Vals()...)
            }
            log.Printf("k=%q vals=%q", k, vals)

            // this may even be optional
            if scanner.Err() != nil {
                return scanner.Err()
            }
        }
        return scanner.Err()
    })
    if err != nil {
        panic(err)
    }