G'day viffer,

You can do all those date calculations with the built-in modules Time::Piece and Time::Seconds.

Here are examples of the types of things you indicated. Do check the doco: there may be other ways to do these which more closely fit your requirements. 

$ perl -Mstrict -Mwarnings -E '
    use Time::Piece;
    use Time::Seconds;

    my @ordinals = qw{1st 2nd 3rd 4th 5th};
    my @even_odd = qw{even odd};
    my $secs_per_week = 7 * 24 * 60 * 60;
    my $days_from_now = 15;

    my $now = localtime;

    say "Today is: ", $now->strftime;

    if ($now->fullday eq "Tuesday") {
        say "It is the $ordinals[$now->mday / 7] Tuesday of the month.
+";
        say "It is the ",
                int($now->epoch / $secs_per_week), "th Tuesday of the 
+epoch.";
        say "So it is an $even_odd[$now->epoch / $secs_per_week % 2] T
+uesday.";
    }
    else {
        say "Not Tuesday: nothing to do.";
    }

    my $future = $now + ONE_DAY * $days_from_now;
    say "$days_from_now days from now will be: ", $future->strftime;
    say "That is ",
            $future->wdayname =~ /^(?:Sat|Sun)$/ ? "" : "not ", "a wee
+kend.";
'
Today is: Tue, 17 Sep 2013 11:38:22 EST
It is the 3rd Tuesday of the month.
It is the 2280th Tuesday of the epoch.
So it is an even Tuesday.
15 days from now will be: Wed, 02 Oct 2013 11:38:22 EST
That is not a weekend.

[download]

-- Ken

In reply to Re: Dates - which Tuesday is it by kcott
in thread Dates - which Tuesday is it by viffer

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