Question

I’m trying to push an element to the end of this array and I get an error I don’t understand.

main.rb:

require 'shop.rb'
so = Shop.new()
so.get(2)
so.get(1)

shop.rb

class Shop

    def new()
       @products = []
    end


    def get(product)
       @products.push(product)
    end
end

error:

NoMethodError: undefined method `push' for nil:NilClass

Answer 1

In Ruby, the constructor is initialize, not new. But you still use new to create an object, e.g. Checkout.new.

Also, the parentheses after method names are optional, and generally avoided in Ruby when there are no arguments.

def initialize
  @items = []
end