Thank you all monks for your help. I think that , thanks to you, I have found a full DateTime solution : 
    my $Date3= $Date->clone()->set_time_zone('floating')->set_time_zon
+e( 'UTC'    )->set_time_zone( 'Europe/Paris'    );

[download]
That is, remove Paris time zone code, by converting to floating, set UTC time code, then convert by setting Paris time code.

In reply to Re^3: Lost in DateTime ! by pcouderc
in thread Lost in DateTime ! by pcouderc

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