Vorpal.js parameters and arguments

I'm developing a Node.js app and I'm using Vorpal commands. I'm trying to send a value from the command to a function but i can't get it to work. Am I doing anything wrong?

Here is the code:

vorpal
  .command('rollto <num>', 'Rolls to')
  .action(function(num) {
    rollto(num);
  }); 

function rollto(num) {
    bettime = bettimems % 60;
    socket.emit('betting', bettime);
    timer1 = setInterval(function () {
        bettime--;
        socket.emit('betting', bettime);

        if (bettime == 0) {
            socket.emit('random number', num);     
            console.log("Rolled to:" + num + "!!!");
            clearInterval(timer1);
        }
    }, 1000); 
}

The problem is that the function you pass to command's action has different arguments than you assume.

Here is the relevant part from docs:

.command.action(function)

This is the action execution function of a given command. 
It passes in an arguments object and callback.

Actions are executed async and must either call the passed 
callback upon completion or return a Promise.

And here is a working example:

var vorpal = require('vorpal')();

vorpal
.command('rollto <num>', 'Rolls to')
.action(function(arguments, callback) {
    rollto(arguments, callback);
});

function rollto(arguments, callback) {
    var num = arguments.num;  // get 'num' parameter from arguments
    timer1 = setInterval(function () {
        console.log('test');
        console.log(num);
        clearInterval(timer1);
        callback();  // Don't forget to use callback() to notify vorpal
    }, 1000);
}

vorpal
  .delimiter('myapp$')
  .show();

Note that you actually have an async code inside setInterval, so you need to use callback() at the end to notify vorpal that processing is finished.