NAME

Time::PT - objects to store an instant in time

VERSION

This documentation refers to version 1.2.565EHOV of Time::PT, which was released on Sun Jun 5 14:17:24:31 2005.

SYNOPSIS

  use Time::PT;
  
  my $f = Time::PT->new();
  
  print "PipTime is: $f\n";
  print 'The Day-of-Week today is: ', $f->dow(), "\n";

DESCRIPTION

By default, Time::PT stores time descriptions precise to 60ths- of-a-second (0.016667 seconds). The groundwork has been laid for sub-millisecond precision to be included later.

This module has been adapted from the Time::Piece module written by Matt Sergeant <matt@sergeant.org> && Jarkko Hietaniemi <jhi@iki.fi>. Time::PT inherits base data structure && object methods from Time::Fields. PT was written to simplify storage && calculation of encoded, yet distinct && human-readable, time data objects.

This module (Time::PT) does not replace the standard localtime && gmtime functions like Time::Piece but Time::PT objects behave almost identically to Time::Piece objects otherwise (since it was adapted from... I said that already =) ).

2DO

- mk interoperable w/ Time::Seconds objects
- add Time::Zone stuff to use && match zone field reasonably
- replace legacy pt() with tested new() wrapper && fix all apps to use objs instead of local pt()
- flesh out constructor init data parsing && formats supported
- consider epoch functions like _epoch([which epoch]) or individuals like _jinx_epoch()
- mk PT->new able to create from different 'epoch' init types
- fix weird 0 month && 0 day problems
- What else does PT need?

WHY?

The reason I created PT was that I have grown so enamored with Base64 representations of everything around me that I was compelled to write a simple clock utility ( `pt` ) using Base64. This demonstrated the benefit to be gained from time objects with distinct fields && configurable precision. Thus, Time::Fields was written to be the abstract base class for:

  Time::Frame  ( creates objects which represent spans    of time )
      && 
  Time::PT     ( creates objects which represent instants in time )

HOW?

I've made up some silly sentences as mnemonic devices to help me remember every 4th uppercase Base64 character:

  Can      12   Noon       MonthOfYear will be less or equal to 'C'.
  Goats    16   4 PM
  Keep     20   8 PM
  Oats     24   Midnight   HourOfDay   will be less than        'O'.
  Some     28  
  Where?   32              DayOfMonth  will be less than        'W'.

  Cool    COW (Month Hour Day thresholds)
  Guys    Girls
  Keep    Keep
  On      On                   Off
  Sayin'  Sayin'      Sippin'  Sea
  Wassup  WeeDoggies  Water    Water

USAGE

Many of Time::PT's methods have been patterned after the excellent Time::Piece module written by Matt Sergeant <matt@sergeant.org> && Jarkko Hietaniemi <jhi@iki.fi>.

new(<InitType>, <InitData>)

Time::PT's constructor can be called as a class method to create a brand new object or as an object method to copy an existing object. Beyond that, new() can initialize PT objects 3 different ways:

  * <packedB64InitStringImplies'str'>
    eg. Time::PT->new('3C79jo0');
  * 'str'  => <packedB64InitString>
    eg. Time::PT->new('str'  => '0A1B2C3D4E');
  * 'list' => <arrayRef>
    eg. Time::PT->new('list' => [0, 1, 2..9]);
  * 'hash' => <hashRef>
    eg. Time::PT->new('hash' => {'jink' => 8, 'year' => 2003})

color(<DestinationColorTypeFormat>)

This is an object member which will join Base64 representations of each field that has been specified in use() && joins them with color-codes or color escape sequences with formats for varied uses. Currently available DestinationColorTypeFormats are:

  'ANSI'  # eg. \e[1;32m
  'zsh'   # eg. %{\e[1;33m%}
  'HTML'  # eg. <a href="http://Ax9.Org/pt?"><font color="#FF1B2B">
  '4NT'   # eg. color 09 & 
  'Simp'  # eg. RbobYbGbCbUbPb

pt

This function is the legacy procedural version of my command-line PipTime utility. It will be removed in the near future when the object methods fully replace all the old behavior && have been tested sufficiently.

This function && the following ptcc() are the only functions exported when Time::PT is used.

ptcc(<DestinationColorTypeFormat>)

Returns the Simp color code string appropriate for pt (PipTime) data.

  Format   Returned color code string
   'k'     the background will change along with the foreground for standard
             time-of day elements (ie. hms on a dark blue background)
   'f'     color codes for the expanded pt format 
             (eg. color codes corresponding to Sun Jan  4 12:41:48:13 2004)

This function && the previous legacy pt() are the only functions exported when Time::PT is used.

The following methods allow access to individual fields of Time::PT objects:

  $t->C  or  $t->century
  $t->Y  or  $t->year
  $t->M  or  $t->month
  $t->D  or  $t->day
  $t->h  or  $t->hour
  $t->m  or  $t->minute
  $t->s  or  $t->second
  $t->f  or  $t->frame
  $t->j  or  $t->jink
  $t->z  or  $t->zone

Please see Time::Fields for further description of field accessor methods.

After importing this module, when you use localtime or gmtime in a scalar context, you DO NOT get a special Time::PT object like you would when using Time::Piece. This module relies on a new() constructor instead. The following methods are available on Time::PT objects though && remain as similar to Time::Piece functionality as makes sense.

  $t->frm                 # also as $t->frame && $t->subsecond
  $t->sec                 # also available as $t->second
  $t->min                 # also available as $t->minute
  $t->hour                # 24 hour
  $t->mday                # also available as $t->day_of_month
  $t->mon                 # 1 = January
  $t->_mon                # 0 = January
  $t->monname             # Feb
  $t->month               # same as $t->mon
                 # *NOTE* The above definition ( of $t->month() ) is 
                 # different from the Time::Piece interface which defines
                 # month() the same as monname() instead of mon().
  $t->fullmonth           # February
  $t->year                # based at 0 (year 0 AD is, of course 1 BC)
  $t->_year               # year minus 1900
  $t->yy                  # 2 digit year
  $t->wday                # 1 = Sunday
  $t->_wday               # 0 = Sunday
  $t->day_of_week         # 0 = Sunday
  $t->wdayname            # Tue
  $t->day                 # same as mday
                 # *NOTE* Similar to month(), I've defined day() 
                 # differently from Time::Piece which makes it the same
                 # as wdayname() instead of mday().
  $t->fullday             # Tuesday
  $t->yday                # also available as $t->day_of_year, 0 = Jan 01
  $t->isdst               # also available as $t->daylight_savings

The following functions return a list of the named fields. The return value can be joined with any desirable delimiter like:

  join(':', $t->hms);
  join($t->time_separator, $t->hms);

but the functions also can take a list of parameters to update the corresponding named fields like:

  $t->YMD( 2003, 12, 8 ) # assigns new date of December 8th, 2003 to $t

Following are some useful functions && comments of sample return values:

  $t->hms                 # [12, 34, 56]
  $t->hmsf                # [12, 34, 56, 12]
  $t->time                # same as $t->hmsf

  $t->ymd                 # [2000,  2, 29]
  $t->date                # same as $t->ymd
  $t->mdy                 # [ 2, 29, 2000]
  $t->dmy                 # [29,  2, 2000]
  $t->datetime            # 2000-02-29T12:34:56            (ISO 8601)
  $t->expand              # Tue Feb 29 12:34:56:12 2000
  $t->cdate               # same as $t->expand
  $t->compress            # 02TCYuC
  "$t"                    # same as $t->compress

  $t->is_leap_year        # true if it is
  $t->month_last_day      # 28-31

  $t->time_separator($s)  # set the default separator (default ":")
  $t->date_separator($s)  # set the default separator (default "-")
  $t->day_list(@days)     # set the default weekdays
  $t->mon_list(@days)     # set the default months

Local Locales

Both wdayname() && monname() can accept the same list parameter as day_list() && mon_list() respectively for temporary help with simple localization.

  my @days = ( 'Yom Rishone', 'Yom Shayni', 'Yom Shlishi', 'Yom Revi\'i', 
               'Yom Khahmishi', 'Yom Hashishi', 'Shabbat' );

  my $hebrew_day = pt->wdayname(@days);
                 # pt->monname() can be used similarly

To update the global lists, use:

  Time::PT::day_list(@days);
    &&
  Time::PT::mon_list(@months);

Calculations

PT object strings (both in normal initialization && printing) grow left-to-right starting from the Year to specify whatever precision you need while Frame objects grow right-to-left from the frame field.

It's possible to use simple addition and subtraction of objects:

  use Time::Frame;
  
  my $cur_pt       = Time::PT->new();# Dhmsf
  my $one_week     = Time::Frame->new('70000');
  my $one_week_ago = $cur_pt - $one_week;

If a calculation is done with a raw string parameter instead of an instantiated object, the most likely appropriate object constructor is called on it. These init strings must adhere to the implied 'str' format for auto-creating objects; I aim to support a much wider array of operations && to make this module smoothly interoperate with both Time::Piece && Time::Seconds someday but not yet.

  my $cur_pt             = Time::PT->new();
  my $half_hour_from_now = $cur_pt + 'U00';

The following are valid (where $t0 and $t1 are Time::PT objects && $f is a Time::Frame object):

  $t0 - $t1;  # returns Time::Frame object
  $t0 - '63'; # returns Time::PT object
  $t0 + $f;   # returns Time::PT object

Comparisons

All normal numerical && string comparisons should work reasonably on Time::PT objects:

  "<",  ">",  "<=", ">=", "<=>", "==" &&  "!="
  "lt", "gt", "le", "ge", "cmp", "eq" and "ne"

YYYY-MM-DDThh:mm:ss

The ISO 8601 standard defines the date format to be YYYY-MM-DD, and the time format to be hh:mm:ss (24 hour clock), and if combined, they should be concatenated with date first and with a capital 'T' in front of the time.

Week Number

The ISO 8601 standard specifies that weeks begin on Monday and the first week of the year is the one that includes both January 4th and the first Thursday of the year. In other words, if the first Monday of January is the 2nd, 3rd, or 4th, the preceding days are part of the final week of the prior year. Week numbers range from 1 to 53.

NOTES

Whenever individual Time::PT attributes are going to be printed or an entire object can be printed with multi-colors, the following mapping should be employed whenever possible:

           D      Century -> DarkRed
           A      Year    -> Red
           T      Month   -> Orange
           E      Day     -> Yellow
                   hour   -> Green
            t      minute -> Cyan
            i      second -> Blue
            m      frame  -> Purple
            e      jink   -> DarkPurple
                   zone   -> Grey or White

Please see the color() member function in the USAGE section.

There's some weird behavior for PipTimes created with a zero month or day field since both are 1-based. I aim to fix all these bugs but be warned that this issue may be causing math errors for a bit.

I hope you find Time::PT useful. Please feel free to e-mail me any suggestions || coding tips || notes of appreciation ("app-ree-see-ay-shun"). Thank you. TTFN.

CHANGES

Revision history for Perl extension Time::PT:

- 1.2.565EHOV Sun Jun 5 14:17:24:31 2005

* updated test.pl to work properly with Build.PL as well as Makefile.PL

* updated License, minor version, && precision description

- 1.0.42M3ChX Sun Feb 22 03:12:43:33 2004

* added 4NT option to color codes in Fields && color() members in Frame && PT

* updated POD links && CHANGES chronology

- 1.0.41M4cZH Thu Jan 22 04:38:35:17 2004

* moved pt, fpt, && lspt into bin/ for packaging as EXE_FILES

* added Time::Frame::total_frames method

- 1.0.418BGcv Thu Jan 8 11:16:38:57 2004

* moved Curses::Simp::ptCC into Time::PT::ptcc for PipTime-specific Simp Color Codes

* created Time::Fields::_field_colors (centralized base class color codes) && updated Frame && PT _color_fields

* added HOW? POD section for mnemonics

- 1.0.3CVL3V4 Wed Dec 31 21:03:31:04 2003

* changed PREREQ to not have lib files from this pkg

- 1.0.3CQ8ibf Fri Dec 26 08:44:37:41 2003

* fixed typo && hardcoded path in VERSION_FROM of gen'd Makefile.PL

- 1.0.3CNNQHc Tue Dec 23 23:26:17:38 2003

* combined Fields, Frame, && PT into one pkg

- 1.0.3CCA2VC Fri Dec 12 10:02:31:12 2003

* removed indenting from POD NAME section

- 1.0.3CBIQv7 Thu Dec 11 18:26:57:07 2003

* updated test.pl to use normal comments

- 1.0.3CB7Vxh Thu Dec 11 07:31:59:43 2003

* added HTML color option && prepared for release

- 1.0.3CA8ipi Wed Dec 10 08:44:51:44 2003

* built class to inherit from Time::Fields && mimic Time::Piece

- 1.0.37VG26k Thu Jul 31 16:02:06:46 2003

* original version

INSTALL

Please run:

    `perl -MCPAN -e "install Time::PT"`

or uncompress the package && run the standard:

    `perl Makefile.PL; make; make test; make install`

FILES

Time::PT requires:

Carp to allow errors to croak() from calling sub

Math::BaseCnv to handle simple number-base conversion

Time::DayOfWeek also stores global day && month names

Time::DaysInMonth

Time::Fields to provide underlying object structure

Time::Frame to represent spans of time

Time::PT uses (if available):

Time::HiRes to provide subsecond time precision

Time::Local to turn epoch seconds back into a real date

Time::Zone not utilized yet

SEE ALSO

Time::Frame

LICENSE

Most source code should be Free! Code I have lawful authority over is && shall be! Copyright: (c) 2002-2005, Pip Stuart. Copyleft : This software is licensed under the GNU General Public License (version 2). Please consult the Free Software Foundation (http://FSF.Org) for important information about your freedom.

AUTHOR

Pip Stuart <Pip@CPAN.Org>