/ 
Data-CSel-WrapStruct-0.004
River stage two • 6 direct dependents • 11 total dependents
/ Data::CSel::WrapStruct

NAME

Data::CSel::WrapStruct - Wrap data structure into a tree of objects suitable for use with Data::CSel

VERSION

This document describes version 0.004 of Data::CSel::WrapStruct (from Perl distribution Data-CSel-WrapStruct), released on 2019-07-29.

SYNOPSIS

use Data::CSel qw(csel);
use Data::CSel::WrapStruct qw(wrap_struct);

my $data = [
    0,
    1,
    [2, ["two","dua"], {url=>"http://example.com/two.jpg"}, ["even","prime"]],
    3,
    [4, ["four","empat"], {}, ["even"]],
];

my $tree = wrap_struct($data);
my @nodes = csel(":root > * > *:nth-child(4) > *", $tree);
my @tags = map { $_->value } @nodes; # -> ("even", "prime", "even")

Arrays are wrapped in a Data::CSel::WrapStruct::Array, hashes in a Data::CSel::WrapStruct::Hash, and so on. So if you are using type selectors, you might want to add Data::CSel::WrapStruct into class_prefixes for convenience:

my @hashes = map {$_->value} csel({class_prefixes=>["Data::CSel::WrapStruct"]}, "Hash", $tree);
# -> ({url=>"http://example.com/two.jpg"}, {})

The wrapper objects provide some methods, e.g.:

my @empty_hashes = map {$_->value} csel({class_prefixes=>["Data::CSel::WrapStruct"]}, "Hash[length=0]", $tree);
# -> ({})

Refer to their respective documentation for the list of methods available.

Some more examples:

[map {$_->value} csel({class_prefixes=>["Data::CSel::WrapStruct"]}, "Scalar[value >= 3]")]
# -> (3, 4)

DESCRIPTION

This module provides wrap_struct() which creates a tree of objects from a generic data structure. You can then perform node selection using Data::CSel's csel().

You can retrieve the original value of data items by calling value() method on the tree nodes.

FUNCTIONS

None exported by default, but exportable.

wrap_struct($data) => tree

Wrap a data structure using a tree of objects.

Currently cannot handle recursive structure.

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/Data-CSel-WrapStruct.

SOURCE

Source repository is at https://github.com/perlancar/perl-Data-CSel-WrapStruct.

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=Data-CSel-WrapStruct

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.

SEE ALSO

Data::CSel

AUTHOR

perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2019, 2016 by perlancar@cpan.org.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.