1RDF::Trine::Iterator(3)User Contributed Perl DocumentatioRnDF::Trine::Iterator(3)
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6 RDF::Trine::Iterator - Iterator class for SPARQL query results
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9 This document describes RDF::Trine::Iterator version 1.019.
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12 use RDF::Trine::Iterator;
13 my $iterator = RDF::Trine::Iterator->new( \&data, 'bindings', \@names );
14 while (my $row = $iterator->next) {
15 my @vars = keys %$row;
16 # do something with @vars
17 }
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20 "new ( \@results, $type, \@names, %args )"
21 "new ( \&results, $type, \@names, %args )"
22 Returns a new SPARQL Result interator object. Results must be
23 either an reference to an array containing results or a CODE
24 reference that acts as an iterator, returning successive items when
25 called, and returning undef when the iterator is exhausted.
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27 $type should be one of: bindings, boolean, graph.
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29 "type"
30 Returns the underlying result type (boolean, graph, bindings).
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32 "is_boolean"
33 Returns true if the underlying result is a boolean value.
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35 "is_bindings"
36 Returns true if the underlying result is a set of variable
37 bindings.
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39 "is_graph"
40 Returns true if the underlying result is an RDF graph.
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42 "to_string ( $format )"
43 Returns a string representation of the stream data in the specified
44 $format. If $format is missing, defaults to XML serialization.
45 Other options are:
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47 http://www.w3.org/2001/sw/DataAccess/json-sparql/
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49 "from_string ( $xml )"
50 Returns a new iterator using the supplied XML string in the SPARQL
51 XML Results format.
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53 "from_bytes ( $xml )"
54 Returns a new iterator using the supplied XML byte sequence (note:
55 not character data) in the SPARQL XML Results format.
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57 "from_json ( $json )"
58 "next_result"
59 "next"
60 Returns the next item in the stream.
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62 "peek"
63 Returns the next value from the iterator without consuming it. The
64 value will remain in queue until the next call to "next".
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66 "current"
67 Returns the current item in the stream.
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69 "end"
70 "finished"
71 Returns true if the end of the stream has been reached, false
72 otherwise.
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74 "open"
75 Returns true if the first element of the stream has been retrieved,
76 false otherwise.
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78 "close"
79 Closes the stream. Future attempts to retrieve data from the stream
80 will act as if the stream had been exhausted.
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82 "concat ( $stream )"
83 Returns a new stream resulting from the concatenation of the
84 referant and the argument streams. The new stream uses the stream
85 type, and optional binding names and "<%args"> from the referant
86 stream.
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88 "seen_count"
89 Returns the count of elements that have been returned by this
90 iterator at the point of invocation.
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92 "get_boolean"
93 Returns the boolean value of the first item in the stream.
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95 "get_all"
96 Returns an array containing all the items in the stream.
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98 "construct_args"
99 Returns the arguments necessary to pass to a stream constructor to
100 re-create this stream (assuming the same closure as the first
101 argument).
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103 "each ( \&callback )"
104 Calls the callback function once for each item in the iterator,
105 passing the item as an argument to the function. Any arguments to
106 "each" beyond the callback function will be passed as supplemental
107 arguments to the callback function.
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110 "sgrep { COND } $stream"
111 "smap { EXPR } $stream"
112 "swatch { EXPR } $stream"
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115 JSON
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117 Scalar::Util
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119 XML::SAX
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122 Please report any bugs or feature requests to through the GitHub web
123 interface at <https://github.com/kasei/perlrdf/issues>.
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126 Gregory Todd Williams "<gwilliams@cpan.org>"
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129 Copyright (c) 2006-2012 Gregory Todd Williams. This program is free
130 software; you can redistribute it and/or modify it under the same terms
131 as Perl itself.
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135perl v5.28.1 2018-01-05 RDF::Trine::Iterator(3)