# Filters **URL:** \ **Category:** Rails\ **Created:** [July 3, 2008, 10:29am UTC](https://www.ruby-forum.com/t/filters/142088 "2008-07-03T10:29:49Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![jschank](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/96bed5/32.png) [@jschank](https://www.ruby-forum.com/u/jschank)\ **Post date:** [July 3, 2008, 10:29am UTC](https://www.ruby-forum.com/t/filters/142088/1 "2008-07-03T10:29:49Z")
Hello, I’m new to rails and ruby. I’m reading Simply Rails 2, and working through the chapters to learn how to use rails. – backstory – We’re on chapter 8 or so where we are learning about filters. At this step we are to add a before\_filter, like so: before\_filter :login\_required, :only =\> [:new, :create] I’ve looked around for details, but the rails docs offer this: before\_filter(\*filters, &block) Alias for append\_before\_filter and: append\_before\_filter(\*filters, &block) The passed filters will be appended to the filter\_chain and will execute before the action on this controller is performed. This method is also aliased as before\_filter – actual question – What I want to know is: Given this documentation, how would a user know that there is an :only, and an :except parameter, and what they take? Is it some ruby feature of &block paramters that I can toss in a hash? How do I find out what the valid keys are for such hash, and what they do? Thanks, John Schank ---
**Author:** ![jschank](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/96bed5/32.png) [@jschank](https://www.ruby-forum.com/u/jschank)\ **Post date:** [July 3, 2008, 11:06am UTC](https://www.ruby-forum.com/t/filters/142088/2 "2008-07-03T11:06:14Z")
On 3 Jul 2008, at 07:05, jschank wrote: > – actual question – > > What I want to know is: Given this documentation, how would a user > know that there is an :only, and an :except parameter, and what they > take? > You probably wouldn’t. :only and :except should be arrays of actions > that filter should apply or not apply to. > Some thing has gone funny with the docs on [api.rubyonrails.org](http://api.rubyonrails.org), as > there’s a whole swathe of info about filters that has gone. You can > still read it here. > Is it some ruby feature of &block paramters that I can toss in a hash? > How do I find out what the valid keys are for such hash, and what they > do? No, the &block stuff gives the method any block specified as a proc object. the magic hash parameter is swallowed up by the parameter with a splat Fred ---
**Author:** ![jschank](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/96bed5/32.png) [@jschank](https://www.ruby-forum.com/u/jschank)\ **Post date:** [July 3, 2008, 6:41pm UTC](https://www.ruby-forum.com/t/filters/142088/3 "2008-07-03T18:41:35Z")
Ah. Ok. Thanks for the reply. I come from Java development, and I’ve been using Netbeans as my rails IDE (though I know you don’t actually need one) And one thing I really miss is the abilty to highlight a method and get pop up help about it. Or to have intellisense which shows the possible alternatives. Following a tutorial book is all well and good, but it only shows you how to do specifically what the tutorial shows. I’m finding it a little bit difficult to see alternatives and possibilities in the Rails / Ruby docs. I suppose I’ll be browsing here a lot more. 🙂 On Jul 3, 5:05 am, Frederick C. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![jschank](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/96bed5/32.png) [@jschank](https://www.ruby-forum.com/u/jschank)\ **Post date:** [July 3, 2008, 7:00pm UTC](https://www.ruby-forum.com/t/filters/142088/4 "2008-07-03T19:00:57Z")
On 3 Jul 2008, at 17:40, jschank wrote: > Ah. Ok. > Thanks for the reply. > > I come from Java development, and I’ve been using Netbeans as my rails > IDE (though I know you don’t actually need one) And one thing I really > miss is the abilty to highlight a method and get pop up help about it. > Or to have intellisense which shows the possible alternatives. The problem in this particular case is that the documentation got mashed. I don’t know netbeans, but i’d be surprised if it didn’t have some sort of documentation lookup. I use textmate as my editor and if I hit control H I get the rdoc for the method in question Fred