employee.rb

#-*- encoding: utf-8 -*-
class Employee
  attr_reader :name
  attr_accessor :salary, :title

  def initialize(name, title, salary)
    @name = name
    @title = title
    @salary = salary
  end
end

fred = Employee.new("Fred Flinstone", "Crane operator", 30000.0)
# Так как мы сделали attr_accessor к полю salary, можно написать
fred.salary = 35000.0