Method chaining by message sending

method_chaining_helper.rb

class Object
  def send_each(*methods)
    methods.inject(self) do |o, m| 
      o.respond_to?(m) ? o.public_send(m) : o
    end
  end
end

class MethodSequence
  def document_download_cells(object, name, icon_path)
    icon = content_tag(:td, image_tag(icon_path))
    title = content_tag(:td, name)
    methods = [:content, :url]
    link = nil
    if url = chain(object, methods)
      link = content_tag(:td, link_to("Download", url))
    end

    [icon, title, link].sum
  end

  def chain(object, methods)
    methods.each do |sym|
      if object.send(sym)
        object = object.send(sym)
      else
        return nil
      end
    end
    object
  end

  # def send_each(methods, object)
  #   methods.inject(object) {|o, m| o.send(m) }
  # end
end

class SomeObject
  def foo
    "FOO"
    return nil
  end

  def bar
    "bar"
  end

  def baz
    "baz"
  end
end

# result = MethodSequence.new.send_each([:foo, :downcase, :reverse], SomeObject.new)
# puts result

result = SomeObject.new.send_each(:foo, :downcase, :reverse)
puts result

result = "Foo".send_each(:downcase, :not_here, :reverse)
result = "Foo".downcase.reverse
puts result

# obj = SomeObject.new
# obj.foo.bar.baz.downcase <-- chain?

# obj.foo
# obj.bar
# obj.bax
# obj.downcase