coerce.rb

class Vector
  def initialize(x, y)
    @x, @y = x, y
  end
 
  def *(value)
    self.class.new(@x * value, @y * value)
  end
 
  def to_s
    "#{@x}, #{@y}"
  end

  def coerce(other)
    [self, other]
  end
end
 
v = Vector.new(3, 5)
puts v
puts v * 3
puts 3 * v