print "pre if() statement\n"

if(@ARGV == 0) {
  my $n = 1;
  while(<DATA>) {
    print $n++, $_;
  }
}

print "post if() statement\n";

__DATA__
this
totally
works

##</code><code>##

pre if() statement
1: this
2: totally
3: works
post if() statement