NAME

NAME
RDF::Query::Functions::Buzzword::DateTime - plugin for buzzword.org.uk
datetime functions

SYNOPSIS
use RDF::TrineX::Functions -shortcuts;
use RDF::Query;

my $data = rdf_parse(<<'TURTLE', type=>'turtle', base=>$baseuri);
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

<http://tobyinkster.co.uk/#i>
foaf:birthday "1980-06-01"^^<http://www.w3.org/2001/XMLSchema#date> .
TURTLE

my $query = RDF::Query->new(<<'SPARQL');
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX util: <http://buzzword.org.uk/2011/functions/util#>
PREFIX dt: <http://buzzword.org.uk/2011/functions/datetime#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT
(dt:now() AS ?now)
(dt:today() AS ?today)
?bday
(dt:format_duration(dt:difference(dt:now(), ?bday), "%Y years, %m months") AS ?age)
(dt:add(?bday, "P10Y"^^xsd:duration) AS ?tenthbday)
(dt:strtotime("yesterday morning"@en) AS ?yesterdaymorning)
(dt:strftime(?bday, "%a, %d %b %Y"@en) AS ?fmtbday)
(dt:strtodate("1/6/1980"@en-gb) AS ?guessbday)
WHERE
{
?person foaf:birthday ?bday .
}
SPARQL

print $query->execute($data)->as_xml;

DESCRIPTION
This is a plugin for RDF::Query providing a number of extension
functions for dates and times.

* http://buzzword.org.uk/2011/functions/datetime#add

Given an xsd:dateTime or xsd:date, and an xsd:duration, adds the
duration to the datetime. Returns an xsd:date if it was passed an
xsd:date and the xsd:duration didn't specify any hours, minutes or
seconds. Returns an xsd:dateTime otherwise.

* http://buzzword.org.uk/2011/functions/datetime#difference

Given two xsd:dateTime or xsd:date literals, returns an xsd:duration
representing the difference between them.

* http://buzzword.org.uk/2011/functions/datetime#format_duration

Given an xsd:duration and a literal formatting string, returns a
formatted duration. See DateTime::Format::Duration.

* http://buzzword.org.uk/2011/functions/datetime#now

Returns the current xsd:dateTime, with supposed nanosecond
precision. If called multiple times in the same SPARQL query, will
always return the same instant.

* http://buzzword.org.uk/2011/functions/datetime#strftime

Takes a xsd:datetime and a literal formatting string and returns a
formattted date. See DateTime.

* http://buzzword.org.uk/2011/functions/datetime#strtodate

Attempts to parse an arbitrary literal using natural language and
convert it into an xsd:date. Smart enough to tell the difference
between "1/6/1980"@en-us and "1/6/1980"@en-gb.

Can safely be passed an existing xsd:date or xsd:dateTime.

* http://buzzword.org.uk/2011/functions/datetime#strtotime

As per "strtodate" but returns an xsd:dateTime.

"add", "difference" and "strftime" all implicitly call "strtotime"
on their xsd:dateTime arguments, which means they don't need to be
given strict xsd:date/dateTime input.

* http://buzzword.org.uk/2011/functions/datetime#today

Like "now" but returns an xsd:date.

SEE ALSO
RDF::Query, RDF::Query::Functions::Buzzword::Util.

DateTime.

<http://www.perlrdf.org/>.

AUTHOR
Toby Inkster <[email protected]>.

COPYRIGHT
Copyright 2011-2012 Toby Inkster

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