diff options
Diffstat (limited to 'activerecord/lib/active_record/aggregations.rb')
| -rw-r--r-- | activerecord/lib/active_record/aggregations.rb | 23 |
1 files changed, 15 insertions, 8 deletions
diff --git a/activerecord/lib/active_record/aggregations.rb b/activerecord/lib/active_record/aggregations.rb index 81ddbba51e..c7a329d74d 100644 --- a/activerecord/lib/active_record/aggregations.rb +++ b/activerecord/lib/active_record/aggregations.rb @@ -46,7 +46,7 @@ module ActiveRecord # # def <=>(other_money) # if currency == other_money.currency - # amount <=> amount + # amount <=> other_money.amount # else # amount <=> other_money.exchange_to(currency).amount # end @@ -71,7 +71,7 @@ module ActiveRecord # Now it's possible to access attributes from the database through the value objects instead. If # you choose to name the composition the same as the attribute's name, it will be the only way to # access that attribute. That's the case with our +balance+ attribute. You interact with the value - # objects just like you would any other attribute, though: + # objects just like you would with any other attribute: # # customer.balance = Money.new(20) # sets the Money value object and the attribute # customer.balance # => Money value object @@ -86,6 +86,12 @@ module ActiveRecord # customer.address_street = "Hyancintvej" # customer.address_city = "Copenhagen" # customer.address # => Address.new("Hyancintvej", "Copenhagen") + # + # customer.address_street = "Vesterbrogade" + # customer.address # => Address.new("Hyancintvej", "Copenhagen") + # customer.clear_aggregation_cache + # customer.address # => Address.new("Vesterbrogade", "Copenhagen") + # # customer.address = Address.new("May Street", "Chicago") # customer.address_street # => "May Street" # customer.address_city # => "Chicago" @@ -101,8 +107,8 @@ module ActiveRecord # ActiveRecord::Base classes are entity objects. # # It's also important to treat the value objects as immutable. Don't allow the Money object to have - # its amount changed after creation. Create a new Money object with the new value instead. This - # is exemplified by the Money#exchange_to method that returns a new value object instead of changing + # its amount changed after creation. Create a new Money object with the new value instead. The + # Money#exchange_to method is an example of this. It returns a new value object instead of changing # its own values. Active Record won't persist value objects that have been changed through means # other than the writer method. # @@ -119,7 +125,7 @@ module ActiveRecord # option, as arguments. If the value class doesn't support this convention then +composed_of+ allows # a custom constructor to be specified. # - # When a new value is assigned to the value object the default assumption is that the new value + # When a new value is assigned to the value object, the default assumption is that the new value # is an instance of the value class. Specifying a custom converter allows the new value to be automatically # converted to an instance of value class if necessary. # @@ -172,8 +178,8 @@ module ActiveRecord # with this option. # * <tt>:mapping</tt> - Specifies the mapping of entity attributes to attributes of the value # object. Each mapping is represented as an array where the first item is the name of the - # entity attribute and the second item is the name the attribute in the value object. The - # order in which mappings are defined determine the order in which attributes are sent to the + # entity attribute and the second item is the name of the attribute in the value object. The + # order in which mappings are defined determines the order in which attributes are sent to the # value class constructor. # * <tt>:allow_nil</tt> - Specifies that the value object will not be instantiated when all mapped # attributes are +nil+. Setting the value object to +nil+ has the effect of writing +nil+ to all @@ -191,7 +197,8 @@ module ActiveRecord # # Option examples: # composed_of :temperature, :mapping => %w(reading celsius) - # composed_of :balance, :class_name => "Money", :mapping => %w(balance amount), :converter => Proc.new { |balance| balance.to_money } + # composed_of :balance, :class_name => "Money", :mapping => %w(balance amount), + # :converter => Proc.new { |balance| balance.to_money } # composed_of :address, :mapping => [ %w(address_street street), %w(address_city city) ] # composed_of :gps_location # composed_of :gps_location, :allow_nil => true |