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Attean::API::Iterator(3pm) User Contributed Perl Documentation Attean::API::Iterator(3pm)

NAME

Attean::API::Iterator - Typed iterator

VERSION

This document describes Attean::API::Iterator version 0.021

DESCRIPTION

The Attean::API::Iterator role defines a common API for typed iterators. This package also defines several type-specific iterator roles:
  • Attean::API::TripleIterator
  • Attean::API::QuadIterator
  • Attean::API::MixedStatementIterator
  • Attean::API::ResultIterator

These roles will automatically be applied to iterators during construction when appropriate.

ATTRIBUTES

The following attributes exist:
"item_type"
A string indicating the type of elements returned by the iterator.

REQUIRED METHODS

The following methods are required by the Attean::API::Iterator role:
"next"
Returns the next element from the iterator, or "undef" upon exhaustion.

METHODS

The Attean::API::Iterator role provides default implementations of the following methods:
"elements"
Returns a list of all remaining elements in the iterator.
"map( \&mapper [, $result_type] )"
Returns a new Attean::API::Iterator object with each element mapped using the supplied &mapper function. If the iterator elements are of the same type as those in the referent iterator, only a mapping function is required. Otherwise, the supplied Type::Tiny $result_type object must indicate the new iterator's type information.
"grep( \&filter )"
Returns a new Attean::API::Iterator object that filters elements from the referent iterator based on whether calling "&filter( $element )" for each $element results in a true value.
"offset( $offset )"
Returns the Attean::API::Iterator referent after skipping the first $offset elements.
"limit( $limit )"
Returns a new Attean::API::Iterator object which returns the first $limit elements of the referent.
"materialize"
Returns a new Attean::API::RepeatableIterator object containing all the elements from the referent.
"debug( [$name] )"
Print each item as it is consumed (with the string generated by "as_string"), prepended by $name.

BUGS

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

SEE ALSO

Attean::API::RepeatableIterator

AUTHOR

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

COPYRIGHT

Copyright (c) 2014--2018 Gregory Todd Williams. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
2019-02-13 perl v5.28.1