NAME¶

Attean::API::Iterator - Typed iterator

VERSION¶

This document describes Attean::API::Iterator version 0.034

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--2022 Gregory Todd Williams. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.