How about somthing with Watch in it. This is kinda like the watch functionality of a debugger.

Wandering CPAN a bit lead me to the Hook::PrePostCall which allows you to put an action before and after a subroutine call. The other subroutines in the Control Flow Utilities section are not in a sub package so they just have the base name. So maybe:

• Hook::DataWatcher
• Data::WatchVariable
• Loop::Watch

Very cool module. Any idea of the performance hit?

-ben