diff options
Diffstat (limited to 'activerecord/lib/active_record/attribute_methods.rb')
-rw-r--r-- | activerecord/lib/active_record/attribute_methods.rb | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb index 0d444f0239..5cb536af1f 100644 --- a/activerecord/lib/active_record/attribute_methods.rb +++ b/activerecord/lib/active_record/attribute_methods.rb @@ -39,6 +39,36 @@ module ActiveRecord undefine_attribute_methods end + # Defines an "attribute" method (like +inheritance_column+ or + # +table_name+). A new (class) method will be created with the + # given name. If a value is specified, the new method will + # return that value (as a string). Otherwise, the given block + # will be used to compute the value of the method. + # + # The original method will be aliased, with the new name being + # prefixed with "original_". This allows the new method to + # access the original value. + # + # Example: + # + # class A < ActiveRecord::Base + # define_attr_method :primary_key, "sysid" + # define_attr_method( :inheritance_column ) do + # original_inheritance_column + "_id" + # end + # end + def define_attr_method(name, value=nil, &block) + sing = metaclass + sing.send :alias_method, "original_#{name}", name + if block_given? + sing.send :define_method, name, &block + else + # use eval instead of a block to work around a memory leak in dev + # mode in fcgi + sing.class_eval "def #{name}; #{value.to_s.inspect}; end" + end + end + # Returns MatchData if method_name is an attribute method. def match_attribute_method?(method_name) rebuild_attribute_method_regexp unless defined?(@@attribute_method_regexp) && @@attribute_method_regexp |