class MyBestClass
    def initialize(name, data, options = {})
      @name    = name
      @data    = data
      @options = options
    end

    def some_method
      raise ArgumentError, "No user set" unless options[:user]
      raise ArgumentError, "No blah set" unless options[:blah]

      # ... do something if user & blah was set
    end
  end

gem 'strict_options'

gem install strict_options

require 'strict_options'

require 'strict_options'

class Product
  include StrictOptions

  def initialize(name, options = {})
    @name    = name
    @options = options
    @sku     = options.fetch(:sku,   nil)
    @price   = options.fetch(:price, nil)
    @brand   = options.fetch(:brand, nil)
  end

  def full_name
    strict_options!(:brand, :sku)
    "#{@brand} #{@name} (#{@sku})"
  end

  def dicounted_price
    strict_options!(:price)
    @price * 0.8
  end
end

p = Product.new("iPhone")
p.full_name #=> options :brand, :sku are missing (ArgumentError)
p.discounted_price #=> option :price is missing (ArgumentError)

p = Product.new("iPhone", brand: "Apple", sku: "iphone_6s_16gb", price: 649)
puts p.full_name #=> Apple iPhone (iphone_6s_16gb)
puts p.discounted_price #=> 519.2

class PriceError < StandardError; end

def calculate_sale_price
  strict_options!(:price, exception_class: PriceError,
                        exception_message: "No price!")
end

calculate_sale_price
#=> #<PriceError: No price!>