Enumerate all Rails ActiveRecord::Base model classes.

enum_models.rb

# Add AR::Base class methods for enumerating all the model
# classes in a Rails project.

module ActiveRecord
  class Base
    def self.all_model_classes
      connection.tables.map do |table|
        begin
          klass = Class.const_get(table.classify)
          klass.ancestors.include?(self) ? klass : nil
        rescue
          nil
        end
      end.compact
    end

    def self.each_model_class(&block)
      all_model_classes.each(&block)
    end
  end
end