Having got a handle on 'local our', here's an example showing that compared with '\local our'.

#!/usr/bin/env perl

use 5.022;
use warnings;
use feature 'refaliasing';
no warnings 'experimental::refaliasing';

@::data = (1 .. 3);

say "Data before pop_sum: @::data";
say "Sum of data: ", pop_sum(\@::data);
say "Data after pop_sum: @::data";
say '---';
say "Data before pop_sum_ref: @::data";
say "Sum of data: ", pop_sum_ref(\@::data);
say "Data after pop_sum_ref: @::data";

sub pop_sum {
    local our @data = @{+shift};

    my $total = 0;

    say "\tTotal: $total; Data: @data";

    while (1) {
        $total += pop @data;
        say "\tTotal: $total; Data: @data";
        last if $#data < 0;
    }

    return $total;
}


sub pop_sum_ref {
    \local our @data = shift;

    my $total = 0;

    say "\tTotal: $total; Data: @data";

    while (1) {
        $total += pop @data;
        say "\tTotal: $total; Data: @data";
        last if $#data < 0;
    }

    return $total;
}
[download]

Output:

Data before pop_sum: 1 2 3
    Total: 0; Data: 1 2 3
    Total: 3; Data: 1 2
    Total: 5; Data: 1
    Total: 6; Data: 
Sum of data: 6
Data after pop_sum: 1 2 3
---
Data before pop_sum_ref: 1 2 3
    Total: 0; Data: 1 2 3
    Total: 3; Data: 1 2
    Total: 5; Data: 1
    Total: 6; Data: 
Sum of data: 6
Data after pop_sum_ref:
[download]

So, with 'local our', we can do whatever we want with @data and, once local's scope is exited, @::data gets back its previous values. As we'd expect with local.

However, the usefulness of '\local our' in this scenario eludes me. @::data does not get back its previous values. Changing

sub pop_sum_ref {
    \local our @data = shift;
[download]

to

sub pop_sum_ref {
    \our @data = shift;
[download]

produces exactly the same results.

Perhaps it simply not useful in this scenario. Perhaps its not operating as intended.

Update: I've raised a bug report for the \local our issue. I'll update again when I get a ticket number.

Update2: Got the ticket: [perl #125436]

For those wishing to view this, there may be some issues.

I used the perlbug utility, which appeared to run successfully:

Message sent

Thank you for taking the time to file a bug report!

Please note that mailing lists are moderated, your message may
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[download]

I waited about 10 hours, received no automated response, so followed the above advice and emailed directly.

Thunderbird somehow mangled what was sent: multiple instances of embedding font tags dozens of levels deep. All you'll initially see is:

"Message body is not shown because it is too large."

If you really want to, you can download the text/html content (31.3k) and view it in a browser. However, other than my perl -V output, it mostly contains the same content as you'll find in this thread, so there's little point in doing this unless you really are that interested.