activerecord - Rails 3: how to write DRYer scopes -

i'm finding myself writing similar code in 2 places, once define (virtual) boolean attribute on model, , once define scope find records match condition. in essence,

scope :something, where(some_complex_conditions)  def something?   some_complex_conditions end 

a simple example: i'm modelling club membership; member pays fee, valid in year.

class member < activerecord::base   has_many :payments   has_many :fees, :through => :payments    scope :current, joins(:fees).merge(fee.current)    def current?     fees.current.exists?   end end  class fee < activerecord::base   has_many :payments   has_many :members, :through => :payments    scope :current, where(:year => time.now.year)    def current?     year == time.now.year   end end 

is there dryer way write scopes make use of virtual attributes (or, alternatively, determine whether model matched conditions of scope)?

i'm pretty new rails please point out if i'm doing stupid!

no, there's no better way you're trying (other take note of geraud's comment). in scope you're defining class-level filter generate sql used in restricting results finders return, in attribute you're defining instance-level test run on specific instance of class.

yes, code similar, it's performing different functions in different contexts.