Whiteboard & DryEraseMarker Instance Method Examples

Erase Method

class Whiteboard
  attr_accessor :contents

  def initialize(contents = [])
    @contents = contents
  end
  
  def erase(contents)
    @contents.delete(contents.length)
  end
end


class DryEraseMarker
  attr_reader :color, :capacity
  def initialize(color)
    @color = color
    @capacity = 100
  end

  INK_USE_PER_CHARACTER = 0.01
  def write(contents, whiteboard)
    @capacity = @capacity - (INK_USE_PER_CHARACTER * contents.length)
    whiteboard.contents << contents
  end
  
  def capacity_empty?
    if @capacity =< 0
      true
    else
      false
    end
  end
  
end