Rails - Sep 2005 - Sane Nil Checking W/in If Stmt

So, in trying to do everything the rails way, I am convinced there  
must be a better way to do what I''m trying to accomplish with this
line:

if @session["user"] != nil and @session["user"].role != nil
and
@session["user"].role.name = "admin"

Basically, how can I determine if a) there is a user in the session,  
b) the user has a role, and c) that role happens to be "admin"?  Is  
there a more concise way to do so in Ruby/Rails?

Thanks!

-- Kimball

On Sep 13, 2005, at 12:42 PM, Kimball Larsen wrote:
> So, in trying to do everything the rails way, I am convinced there  
> must be a better way to do what I''m trying to accomplish with this
> line:
>
> if @session["user"] != nil and @session["user"].role !=
nil and
> @session["user"].role.name = "admin"
I''d do:

   if @session["user"] && @session["user"].role
&& @session
["user"].role.name == "admin"

But there may be an even more concise way.

- Jamis

On Sep 13, 2005, at 2:46 PM, Jamis Buck wrote:
>
> On Sep 13, 2005, at 12:42 PM, Kimball Larsen wrote:
>
>> So, in trying to do everything the rails way, I am convinced there 
>> must be a better way to do what I''m trying to accomplish with
this
>> line:
>>
>> if @session["user"] != nil and
@session["user"].role != nil and
>> @session["user"].role.name = "admin"
>
> I''d do:
>
>   if @session["user"] && @session["user"].role
&&
> @session["user"].role.name == "admin"
>
> But there may be an even more concise way.
>
> - Jamis
You could probably say:

if (session[:user].role.name == ''admin'' rescue false)

Which is "horizontally short" (a big feature in _some_ frameworks), if
not a little smelly.
It seems to me that the role.name == ''admin'' part could be
moved into
the user object such
that you''re left with:

if session[:user] && session[:user].is_admin?

If it''s applicable to your situation, you may also verify 
session[:user] in a before_filter
(as is the case with authentication) which could knock out the first 
check there.

-- 
Scott Barron
Lunchbox Software
http://lunchboxsoftware.com
http://lunchroom.lunchboxsoftware.com