CODEWITHSUNDEEP
ruby
BlackHatSamurai
BlackHatSamurai

Reputation: 23483

Using multiple parameters in Ruby

I am trying to figure out the best way to use multiple parameters in Ruby. The problem is that I am using two types of parameters: Event and User. Sometimes the method needs one User:

postAccept.replaceVariables(sally)

Sometimes it needs two Users:

deleteGuest.replaceVariables(sally, tom)

Sometimes it needs an Event and two Users: 

addUserToEvent.replaceVariables(mEvent, tom, sally)

And last, sometimes it needs one Event and one User: 

addnonbookable.replaceVariables(event1, carl)

Here is what I am doing currently in regard to the method:

def replaceVariables(*event)

    if event.size <=2

        if event[0].include?('entryId')
            event1 = event[0]
            my = event[1]
        else
            my = event[0]
            their = event[1]
        end
    else
        event1 = event[0]
        my = event[1]   
        their = event[2]
    end
            ...

The problem is, I can't figure out a way to differentiate between the user and the event. In the example above, I tried to determine if the object has a specific key, or value, but I get NoMethodError.

Can someone tell me what I'm doing wrong, or show me a way to keep things dynamic and flexible?

Upvotes: 0

Views: 298

Answers (2)

Tolik Kukul
Tolik Kukul

Reputation: 2016

def replace_variables(*args)
  events = args.select{|a| a.is_a? Event}
  users = args.select{|a| a.is_a? User}
  #now you have 2 arrays and can manipulate them
  #...
end

Tin Man suggested implementation in 1 line:

def replace_variables(*args)
  events, users = args.group_by{ |p| p.class }.values_at(Event, User)
  #now you have 2 arrays and can manipulate them
  #...
end

Upvotes: 4

Paige Ruten
Paige Ruten

Reputation: 176655

Check if the first argument is an event. If it is, then it is the only event, and the rest are users, and you can shift out the event. Otherwise, all of them are users.

def replaceVariables(*users)
  event = nil
  if users.first.is_a? Event
    event = users.shift
  end
  # ...
end

Upvotes: 1

Related Questions