Rails frameworks over the years - Ruby on Rails Full Tutorial

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How to find what frameworks are available in the current version of Rails? Use the config.frameworks option to get an array of `Symbol`s that represent each framework.
Rails versions in Rails 1.x ActionMailer ActionPack ActionWebService ActiveRecord ActiveSupport Railties
Rails frameworks in Rails 2.x ActionMailer ActionPack ActiveRecord ActiveResource (ActiveWebService was replaced by ActiveResource, and with that, Rails moved from SOAP to REST by default) ActiveSupport Railties
Rails frameworks in Rails 3.x ActionMailer ActionPack ActiveModel ActiveRecord ActiveResource ActiveSupport Railties

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https://develop.horje.com/learn/1434/reference