Why does Ruby need fiber?

Question

Ruby on Rails

Actually the question is in the header. Why is fiber needed in Ruby?

Answer 1

In general, I myself figured out why Fibers are needed - in RUSSIAN speaking, most likely as external iterators, for example like this:

class PhotoClass
  def initialize(media)
    @fibs  = []
    @media = media
    @fib   = fib(media)
  end

  def read
    @fib.resume @media
  end

private
  def fib(media)
    Fiber.new do |media|
      loop do
        stop = true
        (0..media.length).each do |index|
          result = fiber_inner(index).resume media[index].stock_photos if media[index]

          unless result.nil?
            stop = false
            Fiber.yield ({ :index => index, :title => { :group => media[index].title, :image => media[index].stock_photos[result].title }, :url => media[index].stock_photos[result].image.url })
          end
        end
        Fiber.yield nil if stop
      end
    end
  end

protected
  def fiber_inner(num)
    return @fibs[num] if @fibs[num]

    @fibs[num] = Fiber.new do |content|
      content.each_with_index do |(image),index|
        Fiber.yield index
      end
      loop do Fiber.yield nil end
    end
  end
end

We use in the view:

<% loop do %>

                  <% image = @photo.read %>
                  <% break if image.nil? %>

                  <div class="portfolio-box cm<%= image[:index] %>-design">
                    <div class="portfolio-box-container work">
                      <img src="<%= image[:url] %>" alt="" data-at2x="<%= image[:url] %>">
                      <div class="portfolio-box-text">
                        <h3><%= image[:title][:group] %></h3>
                        <p>Краткое описание картинки изобра.</p>
                      </div>
                        <div class="work-bottom">
                          <a class="big-link-2 view-work" href="<%= image[:url]%>"><span class="icon_search"></span></a>
                          <a class="big-link-2" href="/complectation/index"><span class="icon_link"></span></a>
                        </div>

                    </div>
                  </div>
                  <% end %>

Answer 2

then why microflows are needed in erlang and goroutines in golang.

Answer 3

The main difference between Fiber and Thread is that you program the context switch yourself