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     #max_attempts     => 0, # optional, default 0 (retry endlessly)
     #jitter_factor    => 0, # optional, set to positive value to add randomness
     delay             => 2, # required
     #delay_on_success => 0, # optional, default 0
 );

 # 2. log success/failure and get a new number of seconds to delay, timestamp is
 # optional argument (default is current time) but must be monotonically
 # increasing.

 my $secs = $ar->failure(1554652553); # => 2
 my $secs = $ar->success();           # => 0
 my $secs = $ar->failure();           # => 2

=head1 DESCRIPTION

This retry strategy is one of the simplest: it waits X second(s) after each
failure, or Y second(s) (default 0) after a success. Some randomness can be
introduced to avoid "thundering herd problem".

=head1 METHODS


=head2 new

Usage:

 new(%args) -> obj

This function is not exported.

Arguments ('*' denotes required arguments):

=over 4

=item * B<consider_actual_delay> => I<bool> (default: 0)

Whether to consider actual delay.

If set to true, will take into account the actual delay (timestamp difference).
For example, when using the Constant strategy of delay=2, you log failure()
again right after the previous failure() (i.e. specify the same timestamp).
failure() will then return ~2+2 = 4 seconds. On the other hand, if you waited 2
seconds before calling failure() again (i.e. specify the timestamp that is 2
seconds larger than the previous timestamp), failure() will return 2 seconds.
And if you waited 4 seconds or more, failure() will return 0.

=item * B<delay>* => I<ufloat>

Number of seconds to wait after a failure.

=item * B<delay_on_success> => I<ufloat> (default: 0)

Number of seconds to wait after a success.

=item * B<jitter_factor> => I<float>

How much to add randomness.

If you set this to a value larger than 0, the actual delay will be between a
random number between original_delay * (1-jitter_factor) and original_delay *
(1+jitter_factor). Jitters are usually added to avoid so-called "thundering
herd" problem.

=item * B<max_attempts> => I<uint> (default: 0)

Maximum number consecutive failures before giving up.

0 means to retry endlessly without ever giving up. 1 means to give up after a
single failure (i.e. no retry attempts). 2 means to retry once after a failure.
Note that after a success, the number of attempts is reset (as expected). So if
max_attempts is 3, and if you fail twice then succeed, then on the next failure
the algorithm will retry again for a maximum of 3 times.

=back

Return value:  (obj)

=head1 HOMEPAGE

Please visit the project's homepage at L<https://metacpan.org/release/Algorithm-Retry>.

=head1 SOURCE

Source repository is at L<https://github.com/perlancar/perl-Algorithm-Retry>.

=head1 BUGS

Please report any bugs or feature requests on the bugtracker website L<https://rt.cpan.org/Public/Dist/Display.html?Name=Algorithm-Retry>

When submitting a bug or request, please include a test-file or a
patch to an existing test-file that illustrates the bug or desired
feature.

=head1 SEE ALSO

L<Algorithm::Retry>

Other C<Algorithm::Retry::*> classes.

=head1 AUTHOR

perlancar <perlancar@cpan.org>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2019 by perlancar@cpan.org.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut