gistfile1.rb

File.open('foo.rb', 'w') do |file| 
  file.write(%{
    class Foo
      def initialize
      end

      def bar
        1
      end
    end
    })
end

require './foo'

f = Foo.new
p f.bar

File.open('foo.rb', 'w') do |file| 
  file.write(%{
    class Foo
      def initialize
      end

      def bar
        2
      end
    end
    })
end

require './foo'

p 'After require: '
p f.bar
p Foo.new.bar

load 'foo.rb'
p 'After load: '
p f.bar
p Foo.new.bar