This sounds like the observer/observable pattern. There are two implementations that I know of on cpan: Class::Observable which I don't recommend since it has a pretty serious bug, and Class::Publisher which can be used just like Class::Observable but also gives you more options selecting notifications.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Implementing an event-driven object model in Perl by Joost
in thread Implementing an event-driven object model in Perl by jkva

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