CODEWITHSUNDEEP
rubymethods
Zack
Zack

Reputation: 671

How is this instance method accessible in another class

Here is the code:

class Movie

    def initialize(title, rank=0)
        @title = title
        @rank = rank
    end

    def to_s
        "#{@title} has a rank of #{@rank}"
    end

    def thumbs_up
        @rank += 1
    end

    def thumbs_down
        @rank -= 1
    end
end

class Playlist
    def initialize(name)
        @name = name
        @movies = []
    end

    def add_movie(movie)
        @movies << movie
    end

    def play 
        puts "#{@name}'s playlist:"

        @movies.each do |movie|
            movie.thumbs_up
            puts movie
        end
    end
end`

My question is regarding thumbs_up. This code is working, but I'm curious as to how thumbs up is accessible within the play method in the Playlist class. Is this because the movie being added to the array is an instance of Movie, and can thus have thumbs_up called on it? If so, its strange that that method can be called within a different class like that.

Thanks.

Upvotes: 0

Views: 43

Answers (2)

SteveTurczyn
SteveTurczyn

Reputation: 36860

It's not that strange. thumbs_up is a public method of objects in the Movie class, so wherever a movie object resides, you can call thumbs_up on it.

The method is one of the characteristics of a Movie object, which consists of methods and states (states is the information stored in a class object, in the instance variables).

Upvotes: 1

Robert Krzyzanowski
Robert Krzyzanowski

Reputation: 9344

thumbs_up is a public method, and as such, can be invoked from the Movie instance regardless of where the invokation occurs.

Upvotes: 1

Related Questions