########Programming Fundamental########
# If it can happen, it will happen.
# Control your flow so crap can't happen. 
class AnythingElse
  def initialize
    @anything_else = 'anything else'
  end
  def to_s
    return @anything_else
  end
end 
def can_happen(*anything) 
  if anything.length >= 1
    anything.each do |thing|
      if thing && thing != true
        raise "I don't understand " + thing.to_s
      elsif thing == false
        puts "If it is #{thing} it Cannot Happen"
      elsif thing == nil
        puts "If it is nothing it Cannot Exist."
      else 
        puts "If it is #{thing} it Will Happen"
      end
    end
  else
    puts "If it is nothing it Cannot Exist"
  end
end
begin 
  can_happen()
  can_happen(false, nil, true)
  can_happen(AnythingElse.new, 'crap', 'can\'t happen', 0, 0.0, 'true')
rescue Exception => e
  puts e.inspect
  print e.backtrace.join("\n")
else 
  puts "I fully understand!"
ensure 
  puts "You cannot fool me!"
end