sub myfunc {
    my( $this, $that, @those ) = @_;  # Here it may make sense to pull
                                      # in the contents early on for
                                      # simplicity and clarity's sake.
    # Code here....
    # more code here....
    foreach my $alias ( @those ) {    # Note we declare $alias only
                                      # where it's needed.
        # Do some stuff here.
        # Do more stuff...
        my $another = $alias * 5;     # $another is limited to the scope
                                      # of the foreach loop.
        $this += $another;
    }
    while ( my $choice = shift @those ) { # Another tightly scoped var.
        # Do something else.
    }
    return $this
}