Enumerable

gistfile1.rb

class Account

  attr_accessor :name, :balance

  def initialize(name, balance)
    @name = name
    @balance = balance
  end

  def <=>(other)
    @balance <=> other.balance
  end

end

class Portfolio

  include Enumerable

  def initialize
    @accounts = []
  end

  def each(&block)
    @accounts.each(&block)
  end

  def add_account(account)
    @accounts << account
  end

end

portfolio = Portfolio.new
portfolio.add_account Account.new("account1", 100)
portfolio.add_account Account.new("account2", 200)
portfolio.add_account Account.new("account3", 300)

puts portfolio.any? { |account| account.balance > 200 }
puts portfolio.all? { |account| account.balance > 100 }