The View class

view.js.rb

require 'opal-jquery'

class View
  def self.selector= selector
    @selector = selector
  end

  def self.selector
    @selector
  end

  def self.create *args
    Document.ready? { create!(*args) }
    nil
  end

  def self.create! *args
    instance = new(*args)
    if instance.exist?
      instances << instance
      instance.setup
      yield(instance) if block_given?
    end
    instance
  end

  def self.instances
    @instances ||= []
  end

  def initialize(parent = nil, element = nil)
    @element = element || (parent || Element).find(selector)
  end

  attr_reader :element

  def exist?
    element.any?
  end

  def selector
    self.class.selector || raise(ArgumentError, 'missing selector')
  end

  def setup
    # noop
  end
end