in reply to how to find out the date 'Tuesday' for this week

use POSIX 'strftime';

# get today
my $today = time;

# get current day of week
my $dow = (localtime($today))[6];

# get last Sunday (day 0)
my $sunday = $today - (86_400 * $dow);

# get Tuesday (day 2)
my $tuesday = $sunday + (86_400 * 2);

# print Tuesday in a nice format
print strftime "Tuesday is %d %B %Y\n", localtime $tuesday;

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Re: Re: how to find out the date 'Tuesday' for this week
by no_slogan (Deacon) on Sep 04, 2002 at 14:48 UTC
    That is a nice way to do it without needing to install modules. However, it's often better to use a module anyway, because there are many subtle traps with time processing. For example, not all days are 86,400 seconds long, such as those Sundays when we switch between standard and daylight savings time.
[reply]

      Yeah, I was going to add a note to that effect, but I seem to have forgotten.

      Dealing with that isn't much more complex, you just need to use Time::Local and normalise the times to midday. That way you can be sure that subtracting 86,400 seconds will get you to the previous day. Like this:

      use Time::Local;
use POSIX 'strftime';

# get today
my @today = localtime;

# normalise to midday
@today[0 .. 2] = (0, 0, 12);

# get normalised today
my $today = timelocal @today;

# get current day of week
my $dow = (localtime($today))[6];

# get last Sunday (day 0)
my $sunday = $today - (86_400 * $dow);

# get Tuesday (day 2)
my $tuesday = $sunday + (86_400 * 2);

# print Tuesday in a nice format
print strftime "Tuesday is %d %B %Y\n", localtime $tuesday;

      [download]
      --
      <http://www.dave.org.uk>

      "The first rule of Perl club is you do not talk about Perl club."
      -- Chip Salzenberg

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