Re: OO Perl, iterators

Gregory Toomey <nobody@xxxxxxxxxxx> wrote in comp.lang.perl.misc:
> I'm a bit confused about the Perl OO syntax. From my reading "foreach" acts
> as an iterator.

It is a loop construct. An iterator is something that produces
values to iterate over, like <> or "each" in Perl.

> Any somebody tell me in the standard example below:

For all of these, do

my @answers = $query->answer;


> - how to count the total number of $query->answer

my $total = @answers;

> - how to access the i'th answer; $query->answer[$i] does not work

my $i_th = @answers[ $i];

> - how to access a random answer

my $rand_ans = @answers[ rand @answers];

> thanks
> gtoomey
> --
> use Net::DNS;
> my $res = Net::DNS::Resolver->new;
> my $query = $res->query("example.com", "NS");
>
> if ($query) {
> foreach $rr (grep { $_->type eq 'NS' } $query->answer) {
^^^
You're not running under strict! You've been around long enough to
know better.

> print $rr->nsdname, "\n";
> }
> }

Anno
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