This method is deprecated or moved on the latest stable version.
The last existing version (v3.2.13) is shown here.
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.
# 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
