RDF::Trine::Iterator - Iterator class for SPARQL query results
This document describes RDF::Trine::Iterator version 1.016.
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 }
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:
$format
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.
<%args
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.
each
sgrep { COND } $stream
smap { EXPR } $stream
swatch { EXPR } $stream
JSON
Scalar::Util
XML::SAX
Please report any bugs or feature requests to through the GitHub web interface at https://github.com/kasei/perlrdf/issues.
Gregory Todd Williams <gwilliams@cpan.org>
<gwilliams@cpan.org>
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.
To install RDF::Trine, copy and paste the appropriate command in to your terminal.
cpanm
cpanm RDF::Trine
CPAN shell
perl -MCPAN -e shell install RDF::Trine
For more information on module installation, please visit the detailed CPAN module installation guide.