t.pl

use v5.18;

use strict;
use warnings;
use diagnostics;

use Getopt::Long;

sub must($$) {
	my ($name, $val) = @_;
	die "You must pass --$name\n" unless defined $val;
}

sub main() {
	GetOptions(
		'host=s', \my $host,
		'port=i', \my $port,
	);
	must "host", $host;
	must "port", $port;

	say "Host: $host";
	say "Port: $port";
	say "Positional args ", join ' ', @ARGV;
}

main;