NAME
    Date::Set::Timezones - Date set math with timezones and DST

SYNOPSIS
        use Date::Set::Timezone;

        $a = Date::Set::Timezone->event( at => '20020311Z' );      # 20020311

        # TODO! (see timezone.t for some examples)

DESCRIPTION
    Date::Set::Timezone is a module for date/time sets. It allows you to
    generate groups of dates, like "every wednesday", and then find all the
    dates matching that pattern. It also allows operations with timezones
    and daylight saving times.

    This module is part of the Reefknot project http://reefknot.sf.net

    It requires Date::ICal, Set::Infinite, and Date::Set.

    It doesn't include timezones definitions.

TIMEZONE METHODS
  tz

    Translates a set to another timezone. It changes the timezone only. Time
    values are not changed.

        tz( { dst => $new_timezone_set , 
              name => ['STD-1', 'DST-1'], 
              offset => [ 3600, 2*3600 ] } )

    This is a function. It doesn't change it's object. It returns a new
    object.

    tz() without a parameter allows to work in 'local time' or 'UTC' mode
    (remove timezone info).

    There might be conversion errors nearby DST endings because of 'repeated
    times' when time 'goes back'.

  tz_change

    Moves a set to another timezone. It changes both the timezone and time
    values, and adjusts DST.

        tz_change( { dst => $new_timezone_set , 
              name => ['STD-1', 'DST-1'], 
              offset => [ 3600, 2*3600 ] } )

    This is a function. It doesn't change it's object. It returns a new
    object.

    tz_change() without a parameter moves the set to 'UTC'.

DATE::SET METHODS
  new

    new() behaves differently from Date::Set::new() in that:

        $new_set = $set->new();

    keeps timezone info.

  as_string

    as_string() behaves differently from Date::Set::as_string() in that it
    prints timezone/DST info.

    If supplied with a timezone argument, as_string() stringifies the times
    under that timezone.

    as_string(undef) stringifies the set as UTC times.

  offset

    offset() behaves differently from Date::Set::offset() in that times are
    adjusted for timezone/DST.

    Parameter 'utc' specifies how the offset should be calculated:

        utc => 1  # uses UTC time
        utc => 0  # (default) uses clock time (local time); adjusts for timezone/DST

  quantize

    quantize() behaves differently from Date::Set::quantize() in that times
    are adjusted for timezone/DST.

    Parameter 'utc' specifies how the offset should be calculated:

        utc => 1  # uses UTC time
        utc => 0  # (default) uses clock time (local time); adjusts for timezone/DST

AUTHOR
    Flavio Soibelmann Glock <fglock@pucrs.br> with the Reefknot team,
    specially Martijn van Beers.