#!/usr/bin/env perl use strict; use warnings; print "hello world\n";
How to run it:
$ perl hello.pl hello world
strict and warnings
use strictmakes it an error to use certain expressions.
use warningsenables additional warnings for certain expressions.
Both aim to protect the developer from bad old syntax which the Perl interpreter accepts as valid but will most likely cause your code to behave unexpectedly and cause errors that are hard to debug.