Declaring the callback for `next` ouside the callback of `run`.

[neumino]

The current example relies on the fact that fetchNext is declared in the callback of run.

Users can create a unique callback with something like that:

var fetchNext = function(err, row) {
     if (err) {
            if (((err.name === "RqlDriverError") && err.message === "No more rows in the cursor.")) {
                console.log("No more data to process")
            }
            else {
                // handle error
            }
     }
     else {
        // process row
        this.next(fetchNext.bind(this));
    }
}

// later they can do:
query.run(connection, function(err, cursor) {
     if (err) {
         // handle error
    }
    else {
        cursor.next(fetchNext.bind(cursor));
    }
})

Not so many people use next with a cursor, but this can be useful if users want to open multiple feeds on different end points, and always stream back the changes in the same way.