They use to do it all without counting on any additional PM. They look like the first people that came to live to America.

In this script case, she encloses all the code inside a HERE that is assigned to a variable.

Finally,

undef($@);
eval $all_code;
if ($@) {
[download]

and throws any error to the screen...

This is a tough way of programming, but I guess that everybody can learn a lot of it! Please, have a look also at the full documented page. That is also an important part of a good script, I guess : to be well understood.

This won a price some time ago, for being simple and very useful.

(Extreme programming?, nah!)