NAME

       HTML::Microformats::Datatype::Duration - floating periods of time

SYNOPSIS

        my $duration = HTML::Microformats::Datatype::Duration->new($d);
        print "$duration\n";

DESCRIPTION

   Constructors
       "$d = HTML::Microformats::Datatype::Duration->new($duration)"
           Creates a new HTML::Microformats::Datatype::Duration object.

           $duration is a DateTime::Duration object.

       "$d = HTML::Microformats::Datatype::Duration->parse($string, $elem, $context)"
           Creates a new HTML::Microformats::Datatype::Duration object.

           $string is a duration represented in ISO 8601 format, for example: 'P1Y' or
           'PT2H29M58.682S'. $elem is the XML::LibXML::Element being parsed. $context is the
           document context.

           The standard way of representing durations in Microformats is as an ISO 8601 string:

            <abbr class="duration" title="P4DT4H">4 and a half days</abbr>

           This constructor also supports a number of experimental microformat duration patterns.
           ISO-31 class names are supported:

            <div class="duration">
             <span claa="d">4</span> and
             <abbr title="12" class="h">a half</abbr> days.
            </div>

           As are metric/SI measures (in seconds):

            <span class="duration">124 s</span>
            <span class="duration">124</span> seconds

           Or using an hMeasure microformat with no 'item' property, the 'type' property either
           absent or a case-insensitive match of 'duration' and a unit property of
           's'/'sec'/'seconds', 'min'/'minutes', 'h'/'hours' or 'd'/'days'. For example:

            <span class="duration hmeasure">
             <b class="unit">Days</b>: <span class="num">4.5</span>
            </span>

   Public Methods
       "$d->duration"
           Returns a DateTime::Duration object.

       "$d->to_string"
           Returns an ISO 8601 formatted string representing the duration.

       "$d->datatype"
           Returns an the RDF datatype URI representing the data type of this literal.

   Functions
       "compare($a, $b)"
           Compares durations $a and $b. Return values are as per 'cmp' (see perlfunc).

           Note that there is not always a consistent answer when comparing durations. 30 days is
           longer than a month in February, but shorter than a month in January. Durations are
           compared as if they were applied to the current datetime (i.e. now).

           This function is not exported by default.

           Can also be used as a method:

            $a->compare($b);

       "$c = add($a, $b)"
           Adds two durations together.

           This function is not exported by default.

           Can also be used as a method:

            $c = $a->add($b);

       "$c = subtract($a, $b)"
           Subtracts duration $b from $a.

           This function is not exported by default.

           Can also be used as a method:

            $c = $a->subtract($b);

BUGS

       Please report any bugs to <http://rt.cpan.org/>.

SEE ALSO

       HTML::Microformats, HTML::Microformats::Datatype, DateTime::Duration.

AUTHOR

       Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

       Copyright 2008-2012 Toby Inkster

       This library is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.

DISCLAIMER OF WARRANTIES

       THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
       WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
       PURPOSE.