Forum: Ruby on Rails How to test for a Null or empty object?

I have the following action that is supposed to test whether a username
exists or not. It seems that the first condition never fails. I have put
nothing in the params[:l] hash and the first condition executes. Any
ideas?

def index
    @oLogin = User.find_by_login(params[:l])
    if @oLogin.login != nil
      @sLoggedInName = @oLogin.login + ", you've logged in successfully"
    else
      render :controller => 'session'
    end
  end

I think it is @oLogin that you need to test for nil before accessing
@oLogin.login. This is to check whether the find returned anything.

2009/3/10 Chris Gunnels <rails-mailing-list@andreas-s.net>

Chris Gunnels wrote:

> I have the following action that is supposed to test whether a username
> exists or not. It seems that the first condition never fails. I have put
> nothing in the params[:l] hash and the first condition executes. Any
> ideas?
> 
> def index
>     @oLogin = User.find_by_login(params[:l])
>     if @oLogin.login != nil

if @oLogin

You ought to read some Rails tutorials and projects for a while; these 
patterns
must soak in!

Also, nobody around here uses HN like oLogin. We know it's an 'o'bject 
already!

Colin Law wrote:
> I think it is @oLogin that you need to test for nil before accessing
> @oLogin.login. This is to check whether the find returned anything.
> 
> 2009/3/10 Chris Gunnels <rails-mailing-list@andreas-s.net>

Thx...

> Also, nobody around here uses HN like oLogin. We know it's an 'o'bject 
> already!

good point...I come from a PHP background so not everything is an 
object, I just have to get used to that.

>> Also, nobody around here uses HN like oLogin. We know it's an 'o'bject 
>> already!
> 
> good point...I come from a PHP background so not everything is an 
> object, I just have to get used to that.

Ruby offers very flexible syntax, with many different alternatives for 
each
statement, so we generally try to select the sequence that...

     ...most closely resembles English...

...or whatever your favorite human language is.