Hi Ken,

Many thanks for your reply and also the reference link as well.

May I ask a bit further regarding the example code?

my $fetch;
$fetch = sub {

  # Stop if there are no more URLs
  return unless my $url = shift @urls;

  # Fetch the next title
  my $end = $delay->begin;
  $ua->get($url => sub {
    my ($ua, $tx) = @_;
    say "$url: ", $tx->result->dom->at('title')->text;
    $end->();

    # Next request
    $fetch->();
  });
};

# Process two requests at a time
$fetch->() for 1 .. 2;
$delay->wait;

[download]
From the above code example, I believe this is an example of recursion.
There is condition to exit (return unless my $url = shift @urls;) and $fetch is calling itself within the sub $fetch.

I can understand the part with range operators to call how many times of $fetch.
But why if the range operator has been removed, i.e.
$fetch->();
$delay->wait;

[download]
Shouldn't the code process 1 request at a time until all the @urls have been processed?
But from my testing, it will only process the first url and then stop. Could you tell me more about this part?

Thanks,
Ronald

In reply to Re^2: coderef for 1 .. 2? by ronstudio
in thread coderef for 1 .. 2? by ronstudio

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