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#
#     Example script for DateTime::Event::Easter
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use utf8;
use v5.10;
use strict;
use warnings;
use DateTime;
use DateTime::Event::Easter;

my $anzio = DateTime->new(year  => 1944,
                          month =>    1,
                          day   =>   22);
my $easter  = DateTime::Event::Easter->new();
my $trinity = DateTime::Event::Easter->new(day => 'Trinity');

my $easter_dt  = $easter ->following($anzio)->strftime("%A %d %B %Y");
my $trinity_dt = $trinity->following($anzio)->strftime("%a %d %B %Y");

say <<"EOF";

In French, we have a phrase: "À Pâques ou à la Trinité" ("On Easter Sunday
or on Trinity Sunday"), to designate a date which may shift for various
reasons. The best example, maybe the origin of this phrase, is the
song "Malbrouk s'en va en guerre" (Marlborough goes to war), based on
Sir John Churchill, 1st Duke of Marlborough. The song contains the
following verses:

  Il reviendra z-à Pâques, mironton mironton mirontaine,
  Il reviendra z-à Pâques
  Ou à la Trinité.
  Ou à la Trinité...

  He'll come back on Easter, tweedledee, tweedledee, tweedledum,
  He'll come back on Easter
  Or on Trinity Sunday
  Or on Trinity Sunday

Note for non-native French speakers: frequently, songs take liberty
with proper spelling, proper grammar and proper conjugation for
phonetic reasons. This is the case here. The proper spelling would be:

  Il reviendra à Pâques

Another tradition is to pretend that on Good Friday, the bells leave
the church steeples and fly to Rome, where the Pope bless them and
they fly back on Easter Sunday.

Now, about WWII. The American and Commonwealth forces invaded mainland
Italy in September 1943. They made slow progress and they were stuck
on the Gustav line in October 1943.  They executed another amphibious
landing in January 1944 at Anzio and the landing elements were soon
stuck in their beachhead. So the Germans, with their allies and their
puppets, made fun of an invasion that was slower than a snail's pace.

So on Easter, that is, $easter_dt, flyers shaped as bells
were distributed in France by people friendly to the Vichy
regime. These flyers were saying:

  Je reviens de Rome... les Anglais n'y étaient pas encore...
  Alors... à la Trinité ?

  I am back from Rome... The English are not there yet...
  Maybe on Trinity Sunday?

And when did the recon elements of General Clark's army enter Rome? On
$trinity_dt, that is, on Trinity Sunday.

Sources:

"La Dernière Guerre" (volume 8, page 161), by Eddy Bauer, published in
1975 by "Grange Batelière", republished later by "Éditions Atlas".
No ISBN found.

"Éphémérides de quatre années tragiques" (volume 3, pages 1908 and 2034),
by Pierre Limagne, published in 1987 by "Éditions de Candide".
ISBN 2.904.877.25.8 (the three volumes)
ISBN 2.904.877.28.2 (volume 3)
EOF
