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 <tobyink@cpan.org>.

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.