Thanks ikegami, for the wonderful explanation ! And I really appreciate the example. It really helps a lot.

And thanks for the other suggestions as well. I'm really glad I chanced upon this forum. I did thought of making use of print to try figuring out what the statements would do, but the Internet connection here is really awful. So I gave up downloading Strawberry Perl.

Only could resort to trying to understand the code using Notepad++.