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.
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.
