NAME

DESCRIPTION

In most cases, an example will include two different ways of getting the answer. The first way will be using the new (as of 6.00) OO modules. The second will be using the old-style functional interface.

It should be noted that any time you want to work with alternate time zones, the OO interface is STRONGLY recommended since the functional interface does not preserve time zone information with the date, and may therefore give incorrect results in some cases. However, working in the time zone of the system should give correct results.

It should be noted that, in the examples below, it appears that the OO method often requires more lines of code than the functional interface. There are a number of ways to shorten the OO method, but for the examples, I wanted to include all the steps explicitly.

PARSING A DATE

OO method

   $date = new Date::Manip::Date;
   $err = $date->parse("today");
   $err = $date->parse("1st Thursday in June 1992");
   $err = $date->parse("05/10/93");
   $err = $date->parse("12:30 Dec 12th 1880");
   $err = $date->parse("8:00pm December tenth");
    

Functional

   $date = ParseDate("today");
   $date = ParseDate("1st Thursday in June 1992");
   $date = ParseDate("05/10/93");
   $date = ParseDate("12:30 Dec 12th 1880");
   $date = ParseDate("8:00pm December tenth");
    

The Date::Manip::Date manual has a list of all valid formats.

PARSING AN AMOUNT OF TIME

OO method

   $delta = new Date::Manip::Delta;
   $err = $delta->parse("in 12 hours");
   $err = $delta->parse("-1:30:0");
   $err = $delta->parse("4 business days later");
    

Functional

   $delta = ParseDateDelta("in 12 hours");
   $delta = ParseDateDelta("-1:30:0");
   $delta = ParseDateDelta("4 business days later");
    

TO CALCULATE THE AMOUNT OF TIME BETWEEN TWO DATES

   $datestr1 = "Jan 30 1999 13:00 EST";
   $datestr2 = "2/Mar/1999 15:30:00 +0500";

OO method

   $date1 = new Date::Manip::Date;
   $date2 = $date1->new_date();
   $err = $date1->parse($datestr1);
   $err = $date2->parse($datestr2);
    

To get an exact amount of time between the two dates (expressed only in terms of hours, minutes, seconds), use:

   $delta = $date1->calc($date2);
    

To get an approximate amount of time (expressed in terms of years, months, weeks, etc. in terms that a human would typically think of), use:

   $delta = $date1->calc($date2,"approx");
    

Functional

   $date1 = ParseDate($string1);
   $date2 = ParseDate($string2);
    

To get an exact amount:

   $delta = DateCalc($date1,$date2);
    

and the approximate amount:

   $delta = DateCalc($date1,$date2,1);
    

The Date::Manip::Calc manual has information about these, and other types of calculations.

TO ADD AN AMOUNT OF TIME TO A DATE

   $datestr  = "Jan 30 1999 13:00 EST";
   $deltastr = "12 hours ago";
   $deltastr = "in 3 business days";

OO method

   $date = new Date::Manip::Date;
   $delta = $date->new_delta();
   $date->parse($datestr);
   $delta->parse($deltastr);

   $d = $date->calc($delta);
    

Functional

   $date = DateCalc($datestr,$deltastr);
    

If the delta is a business delta, it will do a business mode calculation.

The Date::Manip::Calc manual has information about these, and other types of calculations.

COMPARE TWO DATES

   $datestr1 = "Jan 30 1999 13:00 EST";
   $datestr2 = "2/Mar/1999 15:30:00 +0500";

OO method

   $date1 = new Date::Manip::Date;
   $date2 = $date1->new_date;
   $date1->parse($datestr1);
   $date2->parse($datestr2);

   $date1->cmp($date2);
      => -1, 0, 1
    

Functional

   $date1 = ParseDate($datestr1);
   $date2 = ParseDate($datestr2);

   Date_Cmp($date1,$date2);
      => -1, 0, 1
    

TO EXTRACT INFORMATION ABOUT A DATE OR DELTA

   $datestr  = "1:24:08 PM EST Feb 3, 1996";
   $deltastr = "12 hours ago";

OO method

   $date = new Date::Manip::Date;
   $delta = $date->new_delta();
   $date->parse($datestr);
   $delta->parse($deltastr);

   $str = $date->printf("It is now %T on %b %e, %Y.");
     =>  "It is now 13:24:08 on Feb  3, 1996."

   $str = $delta->printf("In %hv hours, %mv minutes, %sv seconds");
     => "In -12 hours, 0 minutes, 0 seconds";
    

Functional

   $str = UnixDate($datestr,"It is now %T on %b %e, %Y.");
     =>  "It is now 13:24:08 on Feb  3, 1996."

   $str = Delta_Format($deltastr,"In %hv hours, %mv minutes, %sv seconds");
     => "In -12 hours, 0 minutes, 0 seconds";
    

The Date::Manip::Date manual contains all of the format codes that can be used to extract information from a date. The Date::Manip::Delta manual contains the codes for a delta.

WORKING WITH EPOCH

If you have a date, and you want to find out how many seconds it is after the epoch, you can do it in the following ways:

   $datestr  = "1999-04-30-15:30:00 EDT";
   $secs  = 1234567;

OO method

To find out how many seconds have elapsed on a certain date, you can do the following:

   $date     = new Date::Manip::Date;
   $err      = $date->parse($datestr);

   $str      = $date->printf('%s');
      => number of seconds
    

To find out the date that is a certain number of seconds since the epoch, you can use the following:

   $date  = new Date::Manip::Date;
   $err   = $date->parse("epoch $secs");
    

$date now contains the date wanted (in the local time zone)

Functional

To find out how many seconds have elapsed:

   $str = UnixDate($datestr,'%s');
     => number of seconds
    

To find the date that is a number of seconds since the epoch:

   $date = ParseDateString("epoch $secs");
    

Note that Date::Manip will work with both positive seconds (for dates that have come since the epoch) and negative seconds (for dates that occurred before the epoch).

RECURRING EVENTS

OO method

  # To find the 2nd Tuesday of every month from Jan 1 1999 to Apr 30 1999

  $recur = new Date::Manip::Recur;
  $start = $recur->new_date();
  $end   = $recur->new_date();
  $start->parse("Jan 1 1999");
  $end->parse("Apr 30 1999");

  $recur->parse("0:1*2:2:0:0:0",$start,$end);
  @date = $recur->dates();

  # To find the Monday after Easter in 1997-1999

  $recur = new Date::Manip::Recur;
  $recur->parse("*1997-1999:0:0:0:0:0:0*EASTER,ND1");
  @date = $recur->dates();
    

Functional

  # To find the 2nd Tuesday of every month from Jan 1 1999 to Apr 30 1999
  @date = ParseRecur("0:1*2:2:0:0:0","","Jan 1 1999","Apr 30 1999");

  # To find the Monday after Easter in 1997-1999.
  @date = ParseRecur("*1997-1999:0:0:0:0:0:0*EASTER,ND1");
    

The Date::Manip::Recur manual contains information about recurring events.

WORKING WITH DATES IN ANOTHER LANGUAGE

OO method

   $date = new Date::Manip::Date;
   $date->config("Language","French","DateFormat","non-US");
   $date->parse("1er decembre 1990");
    

Functional

   Date_Init("Language=French","DateFormat=non-US");
   $date = ParseDate("1er decembre 1990");
    

The Date::Manip::Config manual has a list of all supported languages (in the section on the Language config variable). The meaning of the DateFormat config variable is also included.

WORKING WITH TWO DIFFERENT LANGUAGES

OO method

   $date_eng = new Date::Manip::Date;
   $date_eng->config("Language","English","DateFormat","US");

   $date_fre = new Date::Manip::Date;
   $date_fre->config("Language","French","DateFormat","non-US");
    

Use the $date_eng object to do English operations, the $date_fre object to do French operations.

Functional

If you are working with both French and English dates, you can call the following to switch between them:

   Date_Init("Language=French","DateFormat=non-US");
   Date_Init("Language=English","DateFormat=US");
    

This is NOT recommended. Use the OO method instead.

BUGS AND QUESTIONS

SEE ALSO

LICENSE

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