method

instantiate

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What's this?

instantiate(attributes, column_types = {}) public

Given an attributes hash, instantiate returns a new instance of the appropriate class. Accepts only keys as strings.

For example, Post.all may return Comments, Messages, and Emails by storing the record’s subclass in a type attribute. By calling instantiate instead of new, finder methods ensure they get new instances of the appropriate class for each record.

See +ActiveRecord::Inheritance#discriminate_class_for_record+ to see how this “single-table” inheritance mapping is implemented.

Show source

# File activerecord/lib/active_record/persistence.rb, line 66
      def instantiate(attributes, column_types = {})
        klass = discriminate_class_for_record(attributes)
        attributes = klass.attributes_builder.build_from_database(attributes, column_types)
        klass.allocate.init_with('attributes' => attributes, 'new_record' => false)
      end

instantiate

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