You could use this (untested):
# specify which day of week
$recurrence = DateTime::Event::Recurrence->weekly(
days => '7' );
# specify the start and end dates
$now = DateTime->now;
$span = DateTime::Span->from_datetimes(
start => $now->truncate( to => 'month' ),
end => $now );
# count the days
$count = $recurrence->intersection( $span )->count;
In the current implementation this is not efficient for large spans,
because it will make a list of all dates before counting.
- Flavio S. Glock
