# Components going out of style? **URL:** \ **Category:** Rails\ **Created:** [May 24, 2006, 5:28pm UTC](https://www.ruby-forum.com/t/components-going-out-of-style/61506 "2006-05-24T17:28:53Z")\ **Posts on this page:** 3\ **Page:** 2
**Author:** ![nola](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/eb9ed0/32.png) [@nola](https://www.ruby-forum.com/u/nola)\ **Post date:** [September 2, 2006, 8:22pm UTC](https://www.ruby-forum.com/t/components-going-out-of-style/61506/21 "2006-09-02T20:22:55Z")
On Sat, Sep 02, 2006 at 05:34:08PM -0000, DHH wrote: […] > Currently, I believe components just have some performance issues. I’d > encourage you to benchmark with and without to see whether it matters > in your case. And then be on the lookout for other/better ideas that we > could possibly do this. As well as keeping in mind that components are > not a general strategy for compartmentalizing things in Rails, unless > they have this portlet-type flavor we’re discussing. Components have had performance issues in EVERY web platform I’ve used, but usually that’s related to the overhead of an additional request/ssi, instantiating the execution stack, or something related. I suspect (but haven’t dug into the code to confirm) that the right way to approach this might be to stick a continuation somewhere in the rendering path to save all of that setup and use it later to execute an additional action/view pair. – - Adam \*\* Expert Technical Project and Business Management \*\*\*\* System Performance Analysis and Architecture \*\*\*\*\*\* [[http://www.adamfields.com](http://www.adamfields.com) ] [[http://www.aquick.org/blog](http://www.aquick.org/blog) ] … Blog [[Adam Fields Resume](http://www.adamfields.com/resume.html) ]… Experience [[Adam Fields | Flickr](http://www.flickr.com/photos/fields) ] … Photos [[http://www.aquicki.com/wiki](http://www.aquicki.com/wiki) ]…Wiki ---
**Author:** ![nola](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/eb9ed0/32.png) [@nola](https://www.ruby-forum.com/u/nola)\ **Post date:** [April 27, 2007, 7:56pm UTC](https://www.ruby-forum.com/t/components-going-out-of-style/61506/22 "2007-04-27T19:56:44Z")
You can pass vars to a partial using a render option called :locals which points to a hash of names/values to be available as local vars in the partial. > **[ActionController::Base](https://api.rubyonrails.org/classes/ActionController/Base.html#M000267)** > > Action Controllers are the core of a web request in Rails. They are made up of one or more actions that are executed on request and then either it renders a template or redirects to another action. b ---
**Author:** ![nola](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/eb9ed0/32.png) [@nola](https://www.ruby-forum.com/u/nola)\ **Post date:** [April 27, 2007, 3:58pm UTC](https://www.ruby-forum.com/t/components-going-out-of-style/61506/23 "2007-04-27T15:58:31Z")
I understand why partials should be used instead of components, but how can you set clever instance variables that will be used by the partial? The thing is, I prefer not putting business logic into RHTML Basically, instead of writing the following in a view : \<% if(@product.categories.includes?(some\_category)) %\> blablabla \<% end %\> I prefer to keep the view clueless about the model relationships and write something like that instead : \<% if(@display\_some\_section) %\> blablabla \<% end %\> With components, you can execute logic and create any instance variables you need before the view gets rendered. That’s what I liked about them. Is there a way to do the same with partials? By the way, what’s your take about writing code like “if(@product.categories.includes?(some\_category))” in a view? Do you think it is bad design or is it ok as long as you don’t access the model directly (Product.find(…)) ? [Previous page](https://www.ruby-forum.com/t/components-going-out-of-style/61506.md?page=1)