Combining Polymorphic Results from Related Records?

Hello,

I am trying to combine results on two related associations. I have some
models set up as:

class Vendor < ActiveRecord::Base
has_many :vendor_staffs
has_many :vendor_codes, :as => :vendor_codable
end

class VendorStaff < ActiveRecord::Base
belongs_to :vendors
has_many :vendor_codes, :as => :vendor_codable
end

class VendorCode < ActiveRecord::Base
belongs_to :vendor_codable, :polymorphic => true
end

Is there a recommended way to derive this result:

all_vendor_codes = vendor.vendor_codes +
vendor.vendor_staffs.collect.vendor_codes