Named scopes, still needed ?

Wijnand Wiersma vr 25 jun 10

I am wondering what the use cases are for named scope in the Rails3 release.
Just creating a class method which returns an ActiveRelation object gives more clear code and allows for more customisations.

The most obvious use case are old rails 2.3 lambda scopes.
See this example:

named_scope :for, lambda {|author| {:conditions => ["customer_id IS NULL OR customer_id = ?", author.customer_id]} }

You can call this like

Post.for(author) # eg anything that responds to customer

def self.for(testmaker)
 where(:customer_id => testmaker.customer_id)
end

Now it’s not just like calling a method, it actually is a method!

For me this feels far more natural and thanks to Arel magic it just works in the same way too.
You can still chain it as if it was an instance method:

Post.limit(10).for(author)

So if we had to use the hackish lambda scopes regularly (the real need is questionable off course) and now we are better served with a class method: wouldn’t it be far more natural to skip named scopes and just create intelligent class methods?

Rails2:

named_scope :published, :conditions => {:published => true}

scope :published, where(:published => true)

def self.published
 where(:published => true)
end

So unless anybody can give me a compelling reason to use named scopes (lines of code arguments will be rejected) I will proceed on this path.
I think Rails apps should become more Ruby like instead, too much magic hurts my brains.

And remember, everytime you write a lambda scope, god kills an unicorn.

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