class ActiveSupport::Notifications::InstrumentationRegistry

:nodoc:
this class.
The instrumenters for multiple notifiers are held in a single instance of
InstrumentationRegistry.instrumenter_for(notifier)
particular notifier, you can call the following method:
in a particular thread local. To access the Instrumenter object for a
This class is a registry which holds all of the Instrumenter objects

def initialize 

def initialize
  @registry = {}
end

def instrumenter_for(notifier) 

def instrumenter_for(notifier)
  @registry[notifier] ||= Instrumenter.new(notifier)
end