method

add_observer

v3.2.1 - Show latest stable - 0 notes - Class: ActiveModel::Observing::ClassMethods

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What's this?

add_observer(observer) public

Add a new observer to the pool. The new observer needs to respond to ‘update’, otherwise it raises an ArgumentError exception.

Show source

# File activemodel/lib/active_model/observing.rb, line 65
      def add_observer(observer)
        unless observer.respond_to? :update
          raise ArgumentError, "observer needs to respond to `update'"
        end
        observer_instances << observer
      end

add_observer

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