Example of overriding the constructor.

overriding_construction.rb

class Foo
  
  @@cache = {}
  def initialize(id)
    puts "initialize"
    @id = id
  end

  def Foo.new(id)
    if @@cache[id]
      puts "cache hit."
    else
      puts "cache miss."
      @@cache[id] = super    # calls Object.new with original parameters, which in turn calls initialize.
    end
    @@cache[id]
  end
      
  def id
    @id
  end
end

x = Foo.new(1)
y = Foo.new(1)

puts "X = #{x.id}; Y = #{y.id}"

puts x === y