# this is an AR model class
named_scope :privates, :conditions => { :public => false }
named_scope :named_like, lambda { |name| { :conditions => "name LIKE '#{name}%'" }}

# we want to concatenate named_scopes at later points in code
def self.by_privacy_and_name(privates = false, name = nil)
    # we want a named_scope to concatenate other namescopes afterwards
    gs = if privates
           self.privates # with named_scopes everything runs fine
         else
           self.all # here we won't get a NamedScope, instead it'll be an Array
         end
    if name
      gs.named_like name # this blows with Array returned by AR.all
    else
      gs
    end
end