unix.rb

class Symbol
  def |(other)
    self.to_proc | other
  end
end

class Proc
  def |(other)
    proc { |arg| other.to_proc.call(self.call(arg)) }
  end
end

class X
  def initialize(value)
    @value = value
  end

  def foo
    Y.new(@value)
  end
end

class Y
  def initialize(x)
    @x = x
  end

  def bar
    -10 * @x
  end
end

x1, x2 = X.new(1), X.new(-2)

[x1, x2].map(&:foo | :bar)