sub blah {
    my ($foo, $bar, $baz) = @_;
    for my $arg (qw( foo bar baz )) {
        croak("$arg missing/undefined") if !defined(shift);
    }

    ...
}

##</code><code>##

sub blah {
    my ( $foo, $bar, $baz );
    for my $arg ( ( $foo, $bar, $baz ) = @_ ) {
        croak "You forgot something" unless defined $arg;
    }
    do_something;
}

##</code><code>##

sub blah {
    croak "You forgot something" unless all { defined } ( my ( $foo, $bar, $baz ) = @_ );
    do_something;
}