regex - Assign captured group to value, and if no match: assign string

In Perl regex, the documentation says

... in scalar context, $time =~ /(\d\d):(\d\d):(\d\d)/ returns a true
or false value. In list context, however, it returns the list of
matched values ($1,$2,$3)

But how is it that when you provide an alternative option - when no match is found - TRUE or FALSE will be assigned even when in list context?

As an example, I want to assign the matched group to a variable and if not found, use the string value ALL.

my ($var) = $string =~ /myregex/ || 'ALL';

Is this possible? And what about multiple captured groups? E.g.

my ($var1, $var2) = $string =~ /(d.t)[^d]+(d.t)/ || 'dit', 'dat';

Where if the first group isn't matched, 'dit' is used, and if no match for the second is found 'dat'.

Answer

For the first requirement, you can use the ternary operator:

my $string = 'abded';
for my $f ('a' .. 'f') {
    my ($v1) = $string =~ /($f)/ ? ($1) : ('ALL') ;
    say "$f : $v1";

}

Output:

a : a
b : b
c : ALL
d : d
e : e

f : ALL