NAME¶
HTML::CalendarMonth::DateTool - Base class for determining which date package to
use for calendrical calculations.
SYNOPSIS¶
my $date_tool = HTML::CalendarMonth::DateTool->new(
year => $YYYY_year,
month => $one_thru_12_month,
weeknum => $weeknum_mode,
historic => $historic_mode,
datetool => $specific_datetool_if_desired,
);
DESCRIPTION¶
This module attempts to utilize the best date calculation package available on
the current system. For most contemporary dates this usually ends up being the
internal Time::Local package of perl. For more exotic dates, or when week
number of the years are desired, other methods are attempted including
DateTime, Date::Calc, Date::Manip, and the linux/unix 'ncal' or 'cal'
commands. Each of these has a specific subclass of this module offering the
same utility methods needed by HTML::CalendarMonth.
METHODS¶
- new()
- Constructor. Takes the following parameters:
- year
- Year of calendar in question (required). If you are rendering exotic dates
(i.e. dates outside of 1970 to 2038) then something besides Time::Local
will be used for calendrical calculations.
- month
- Month of calendar in question (required). 1 through 12.
- weeknum
- Optional. When specified, will limit class excursions to those that are
currently set up for week of year calculations.
- historic
- Optional. If the the ncal or cal commands are available, use one of them
rather than other available date modules since these utilities accurately
handle some specific historical artifacts such as the transition from
Julian to Gregorian.
- datetool
- Optional. Mostly for debugging, this option can be used to indicate a
specific HTML::CalendarMonth::DateTool subclass for instantiation. The
value can be either the actual utility class, e.g., Date::Calc, or the
name of the CalendarMonth handler leaf class, e.g. DateCalc. Use 'ncal' or
'cal', respectively, for the wrappers around those commands.
There are number of methods automatically available:
- month()
- year()
- weeknum()
- historical()
- datetool()
- Accessors for the parameters provided to "new()" above.
- dow1st()
- Returns the day of week number for the 1st of the "year" and
"month" specified during the call to "new()". Relies
on the presence of "dow1st_and_lastday()". Should be 0..6
starting with Sun.
- lastday()
- Returns the last day of the month for the "year" and
"month" specified during the call to "new()". Relies
on the presence of "dow1st_and_lastday()".
Overridden methods¶
Subclasses of this module must provide at least the "day_epoch()" and
"dow1st_and_lastday()" methods.
- dow1st_and_lastday()
- Required. Provides a list containing the day of the week of the first day
of the month (0..6 starting with Sun) along with the last day of the
month.
- day_epoch()
- Optional unless interested in epoch values for wacky dates. For a given
day, and optionally "month" and "year" if they are
different from those specified in "new()", provide the unix
epoch in seconds for that day at midnight.
If the subclass is expected to provide week of year numbers, three more methods
are necessary:
- dow()
- For a given day, and optionally "month" and "year" if
they are different from those specified in "new()", provide the
day of week number. (1=Sunday, 7=Saturday).
- add_days($days, $delta, $day, [$month], [$year])
- For a given day, and optionally "month" and "year" if
they are different from those specified in "new()", provide a
list of year, month, and day once "delta" days have been
added.
- week_of_year($day, [$month], [$year])
- For a given day, and optionally "month" and "year" if
they are different from those specified in "new()", provide a
list with the week number of the year along with the year. (some days of a
particular year can end up belonging to the prior or following
years).
AUTHOR¶
Matthew P. Sisk, <
sisk@mojotoad.com>
COPYRIGHT¶
Copyright (c) 2010 Matthew P. Sisk. All rights reserved. All wrongs revenged.
This program is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.
SEE ALSO¶
HTML::CalendarMonth(3),
Time::Local(3),
DateTime(3),
Date::Calc(3),
Date::Manip(3),
cal(1)