1Attean::API::Iterator(3U)ser Contributed Perl DocumentatiAotntean::API::Iterator(3)
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6 Attean::API::Iterator - Typed iterator
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9 This document describes Attean::API::Iterator version 0.025
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12 The Attean::API::Iterator role defines a common API for typed
13 iterators. This package also defines several type-specific iterator
14 roles:
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16 · Attean::API::TripleIterator
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18 · Attean::API::QuadIterator
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20 · Attean::API::MixedStatementIterator
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22 · Attean::API::ResultIterator
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24 These roles will automatically be applied to iterators during
25 construction when appropriate.
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28 The following attributes exist:
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30 "item_type"
31 A string indicating the type of elements returned by the iterator.
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34 The following methods are required by the Attean::API::Iterator role:
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36 "next"
37 Returns the next element from the iterator, or "undef" upon
38 exhaustion.
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41 The Attean::API::Iterator role provides default implementations of the
42 following methods:
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44 "elements"
45 Returns a list of all remaining elements in the iterator.
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47 "map( \&mapper [, $result_type] )"
48 Returns a new Attean::API::Iterator object with each element mapped
49 using the supplied &mapper function. If the iterator elements are
50 of the same type as those in the referent iterator, only a mapping
51 function is required. Otherwise, the supplied Type::Tiny
52 $result_type object must indicate the new iterator's type
53 information.
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55 "grep( \&filter )"
56 Returns a new Attean::API::Iterator object that filters elements
57 from the referent iterator based on whether calling "&filter(
58 $element )" for each $element results in a true value.
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60 "offset( $offset )"
61 Returns the Attean::API::Iterator referent after skipping the first
62 $offset elements.
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64 "limit( $limit )"
65 Returns a new Attean::API::Iterator object which returns the first
66 $limit elements of the referent.
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68 "materialize"
69 Returns a new Attean::API::RepeatableIterator object containing all
70 the elements from the referent.
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72 "debug( [$name] )"
73 Print each item as it is consumed (with the string generated by
74 "as_string"), prepended by $name.
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77 Please report any bugs or feature requests to through the GitHub web
78 interface at <https://github.com/kasei/attean/issues>.
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81 Attean::API::RepeatableIterator
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84 Gregory Todd Williams "<gwilliams@cpan.org>"
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87 Copyright (c) 2014--2019 Gregory Todd Williams. This program is free
88 software; you can redistribute it and/or modify it under the same terms
89 as Perl itself.
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93perl v5.30.0 2019-10-31 Attean::API::Iterator(3)