Rails - Jan 2006 - (no subject)

Hello, I''m new to ruby on rails, migrating from php, and I have some
questions:

1- How do I work with null objects without returning the rails error to the
user? Like if I''m searching for a record and no record''s
found, how would I deliver my custom message to the user?

2- How does the ''nil'' object work?

Thanks
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On 16 Jan ''06, at 10:56 AM, thiago jackiw wrote:
> 1- How do I work with null objects without returning the rails  
> error to the user? Like if I''m searching for a record and no  
> record''s found, how would I deliver my custom message to the user?
You could use the :all version of ActiveRecord#find, instead of just  
passing in the record id ? that will return an empty array if no  
record is found, instead of throwing an exception.
> 2- How does the ''nil'' object work?
It''s a bit fancier than a simple nil/null pointer in most other  
languages. It is a real object: the sole instance of a class called  
NilClass, which you can look up in the core library ref. This class  
does pretty much nothing except respond to some boolean and type- 
conversion methods and the very useful ''nil?''.

But for the most part you can treat it just as you would a nil/null  
pointer in PHP or Java or C++ or whatever.

--Jens