instance_vars.rb

class Person  
  attr_accessor :name, :age

  def initialize
    puts "name: #{name}"
    puts "@name: #{@name}"

    name = "David"
    @name = "Tom"

    age = 20
    @age = 30
    
    puts "name: #{name}"
    puts "@name: #{@name}"

    puts "age: #{age}"
    puts "@age: #{@age}"
  end


  def say_name_and_age
    puts "Hello there #{name} - age: #{age}"
    name = "Sam"
    puts "Hello there #{name} - age: #{age}"
  end

  def say_at_name_and_age
    puts "Hello there #{@name} - age: #{@age}"
    @name = "Sam"
    puts "Hello there #{@name} - age: #{@age}"
  end

end


human = Person.new

human.say_name_and_age
human.say_at_name_and_age

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