This module lets you define arbitrary string interpolation semantics, which means that you can control the way variables and other expressions interpolate into your strings. The notation is compact and readable, and you can have as many interpolators as you want. Peruse the source code Dowload the complete package . See a list of clever uses for Interpolation.pm contributed by users . Locked is a module for providing scalar variables that can be locked and unlocked.
Unlocked scalars behave normally.
Locked scalars abort the program if you try to assign to them. This is one of the funniest pieces of software I have ever written. It is an absolute riot. And it is even possibly useful. It is called Identity.pm , but I am looking for a better name.