ActiveRecord::AttributeMethods::ClassMethods

    # File lib/active_record/attribute_methods.rb, line 12
12:       def define_attribute_methods
13:         super(columns_hash.keys)
14:       end

    # File lib/active_record/attribute_methods.rb, line 27
27:       def defined_activerecord_methods
28:         active_record = ActiveRecord::Base
29:         super_klass   = ActiveRecord::Base.superclass
30:         methods =  active_record.public_instance_methods - super_klass.public_instance_methods
31:         methods += active_record.private_instance_methods - super_klass.private_instance_methods
32:         methods += active_record.protected_instance_methods - super_klass.protected_instance_methods
33:         methods.map {|m| m.to_s }.to_set
34:       end

    # File lib/active_record/attribute_methods.rb, line 19
19:       def instance_method_already_implemented?(method_name)
20:         method_name = method_name.to_s
21:         @_defined_class_methods         ||= ancestors.first(ancestors.index(ActiveRecord::Base)).sum([]) { |m| m.public_instance_methods(false) | m.private_instance_methods(false) | m.protected_instance_methods(false) }.map {|m| m.to_s }.to_set
22:         @@_defined_activerecord_methods ||= defined_activerecord_methods
23:         raise DangerousAttributeError, "#{method_name} is defined by ActiveRecord" if @@_defined_activerecord_methods.include?(method_name)
24:         @_defined_class_methods.include?(method_name)
25:       end