The use strict; Statement in Perl

The Perl programming language started as a hack, as a tool that its sole purpose was to fulfill specific needs. When Perl’s popularity grew and more and more people started to use it was already too late to enforce rigid grammar rules. Adding the ‘use strict;’ statement in the beginning of the file will enforce the language rigid rules.

#!/usr/bin/perl
use strict;
use warnings FATAL => 'all';

my $a = 3;
my $b = 4;
my $c = $a+$b;
print($c);