NAME

RDF::Trine::Iterator - Stream (iterator) class for SPARQL query results.

VERSION

This document describes RDF::Trine::Iterator version 0.111.

SYNOPSIS

    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
    }

METHODS

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 in the SPARQL XML Results format.

next

next_result

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.

get_boolean