RDF::Trine::Iterator - Iterator class for SPARQL query results

       Gregory Todd Williams  "<gwilliams@cpan.org>"

       Please   report   any   bugs   or   feature   requests   to   through   the   GitHub   web  interface  at
       <https://github.com/kasei/perlrdf/issues>.

       Copyright (c) 2006-2012 Gregory Todd Williams. This program is free software;  you  can  redistribute  it
       and/or modify it under the same terms as Perl itself.

perl v5.38.2                                       2024-01-13                          RDF::Trine::Iterator(3pm)

       JSON

       Scalar::Util

       XML::SAX

       "sgrep { COND } $stream"
       "smap { EXPR } $stream"
       "swatch { EXPR } $stream"

       "new ( \@results, $type, \@names, %args )"
       "new ( \&results, $type, \@names, %args )"
           Returns  a  new  SPARQL  Result  interator  object.  Results  must be either an reference to an array
           containing results or a CODE reference that acts as an  iterator,  returning  successive  items  when
           called, and returning undef when the iterator is exhausted.

           $type should be one of: bindings, boolean, graph.

       "type"
           Returns the underlying result type (boolean, graph, bindings).

       "is_boolean"
           Returns true if the underlying result is a boolean value.

       "is_bindings"
           Returns true if the underlying result is a set of variable bindings.

       "is_graph"
           Returns true if the underlying result is an RDF graph.

       "to_string ( $format )"
           Returns  a  string representation of the stream data in the specified $format. If $format is missing,
           defaults to XML serialization.  Other options are:

             http://www.w3.org/2001/sw/DataAccess/json-sparql/

       "from_string ( $xml )"
           Returns a new iterator using the supplied XML string in the SPARQL XML Results format.

       "from_bytes ( $xml )"
           Returns a new iterator using the supplied XML byte sequence (note: not character data) in the  SPARQL
           XML Results format.

       "from_json ( $json )"
       "next_result"
       "next"
           Returns the next item in the stream.

       "peek"
           Returns  the  next value from the iterator without consuming it. The value will remain in queue until
           the next call to "next".

       "current"
           Returns the current item in the stream.

       "end"
       "finished"
           Returns true if the end of the stream has been reached, false otherwise.

       "open"
           Returns true if the first element of the stream has been retrieved, false otherwise.

       "close"
           Closes the stream. Future attempts to retrieve data from the stream will act as  if  the  stream  had
           been exhausted.

       "concat ( $stream )"
           Returns  a  new stream resulting from the concatenation of the referant and the argument streams. The
           new stream uses the stream type, and optional binding names and "<%args"> from the referant stream.

       "seen_count"
           Returns the count of elements that have been returned by this iterator at the point of invocation.

       "get_boolean"
           Returns the boolean value of the first item in the stream.

       "get_all"
           Returns an array containing all the items in the stream.

       "construct_args"
           Returns the arguments necessary to pass to a stream constructor to re-create  this  stream  (assuming
           the same closure as the first argument).

       "each ( \&callback )"
           Calls  the  callback  function once for each item in the iterator, passing the item as an argument to
           the function. Any arguments to "each" beyond the callback function will  be  passed  as  supplemental
           arguments to the callback function.

       RDF::Trine::Iterator - Iterator class for SPARQL query results

           use RDF::Trine::Iterator;
           my $iterator = RDF::Trine::Iterator->new( \&data, 'bindings', \@names );
           while (my $row = $iterator->next) {
               my @vars        = keys %$row;
               # do something with @vars
           }

       This document describes RDF::Trine::Iterator version 1.019.