class Treehouse
  def initialize(ladder, happyduckslide, sadsharkslide)
    @ladder = ladder                                                               # => #<StringIO:0x007fb29c0c8a68>
    @happyduckslide  = happyduckslide                                              # => #<IO:<STDOUT>>
    @sadsharkslide = sadsharkslide                                                 # => #<IO:<STDERR>>
  end                                                                              # => :initialize
  
  def ride
    name = @ladder.gets().chomp()                                                  # => "Josh", "Anna Marie"
    if rand(2) == 1                                                                # => true, false
      @happyduckslide.puts("#{name} climbs the ladder, slides into the lake, and swims with the ducks!")  # => nil
    else
      @sadsharkslide.puts("#{name} climbs the ladder, slides into the ocean, and gets devoured by the shark!")   # => nil
    end                                                                            # => nil, nil
  end                                                                              # => :ride
end

require 'stringio'                                                     # => true
ladder         = StringIO.new "Josh\nAnna Marie"                       # => #<StringIO:0x007fb29c0c8a68>
happyduckslide = $stdout                                               # => #<IO:<STDOUT>>
sadsharkslide  = $stderr                                               # => #<IO:<STDERR>>
treehouse      = Treehouse.new(ladder, happyduckslide, sadsharkslide)  # => #<Treehouse:0x007fb29c0c8518 @ladder=#<StringIO:0x007fb29c0c8a68>, @happyduckslide=#<IO:<STDOUT>>, @sadsharkslide=#<IO:<STDERR>>>
treehouse.ride                                                         # => nil
treehouse.ride                                                         # => nil

# There's a super cool new treehouse down the block. 
# It has a ladder that takes a person into the house and two slides that drops them out into a lake.
# Anyone can go for a slide ride.
# 

# >> Josh climbs the ladder and slides into the lake!

# !> Anna Marie climbs the ladder and slides into the lake!