Categories

Parentless Categories

Author: Scott Reilly
Version: 2.3
First released: 2009-06-12
Last update: 2024-08-28
Compatibility: WP 4.6 – 6.6.2
Download: [ zip ]
Description:

Provides a template tag like the_category() to list categories assigned to a post except those that have a child category also assigned to the post.

Extended Description

This plugin provides a template tag which acts as a modified version of WordPress’s built-in template tag, the_category(). the_category() lists all categories directly assigned to the specified post. c2c_parentless_categories() lists those categories, except for categories that are parents to other assigned categories.

For example, assume your category structure is hierarchical and looks like this:

Vegetables
|-- Leafy
|   |-- Broccoli
|   |-- Bok Choy
|   |-- Celery
|-- Fruiting
|   |-- Bell Pepper
|   |-- Cucumber
|   |-- Pumpkin
|-- Podded
|   |-- Chickpea
|   |-- Lentil
|   |-- Soybean

If you directly assigned the categories “Fruiting”, “Cucumber”, and “Pumpkin” to a post, c2c_parentless_categories() would return a list that consists of: “Cucumber”, and “Pumpkin”. Notice that since “Fruiting” was a parent to a directly assigned category, it is not included in the list.

By default, categories are listed as an HTML list. The first argument to the template tag allows you to define a custom separator, e.g. to have a simple comma-separated list of categories: <?php c2c_parentless_categories( ',' ); ?>.

As with categories listed via the_category(), categories that are listed are presented as links to the respective category’s archive page.

Example usage (based on preceding example):

  • <?php c2c_parentless_categories(); ?>

Outputs something like:

<ul><li><a href="http://yourblog.com/category/fruiting/cucumber">Cucumber</a></li>
<li><a href="http://yourblog.com/category/fruiting/pumpkin">Pumpkin</a></li></ul>
  • <?php c2c_parentless_categories( ',' ); ?></ul>

Outputs something like:

<a href="http://yourblog.com/category/fruiting/cucumber">Cucumber</a>, <a href="http://yourblog.com/category/fruiting/pumpkin">Pumpkin</a>

Links: Plugin Homepage | Plugin Directory Page | GitHub | Author Homepage

Developer Documentation

Developer documentation can be found in DEVELOPER-DOCS.md. That documentation covers the template tags and hooks provided by the plugin.

As an overview, these are the template tags provided by the plugin:

  • c2c_parentless_categories() : Outputs the parentless categories.
  • c2c_get_parentless_categories_list() : Returns the list of parentless categories.
  • c2c_get_parentless_categories() : Returns the list of parentless categories for the specified post.

These are the hooks provided by the plugin:

  • c2c_parentless_categories (action), c2c_get_parentless_categories_list, c2c_get_parentless_categories (filters) :
    Allows for an alternative approach to safely invoke each of the identically named functions in such a way that if the plugin were deactivated or deleted, then your calls to the functions won’t cause errors on your site.
  • c2c_parentless_categories_list (filter) :
    Customizes the return value of the c2c_parentless_categories_list() function.
  • c2c_get_parentless_categories_omit_ancestors (filter) :
    Customizes the function argument indicating if ancestor categories of all directly assigned categories (even if directly assigned themselves) should be omitted from the return list of categories.

Find out more at the plugin’s WordPress Plugin Repository page.

Installation

  1. Install via the built-in WordPress plugin installer. Or install the plugin code inside the plugins directory for your site (typically /wp-content/plugins/).
  2. Activate the plugin through the ‘Plugins’ admin menu in WordPress
  3. Optional: Add filters for ‘c2c_parentless_categories_list’ to filter parentless category listing
  4. Use the template tag <?php c2c_parentless_categories(); ?> in a theme template somewhere inside “the loop”

Release Log

2.3 (2024-08-28)

  • Change: Prevent translations from containing unintended markup
  • Change: Add missing inline comment for translators
  • Change: Note compatibility through WP 6.6+
  • Change: Update copyright date (2024)
  • Change: Remove development and testing-related files from release packaging
  • New: Add .gitignore file
  • Unit tests:
    • Allow tests to run against current versions of WordPress
    • New: Add composer.json for PHPUnit Polyfill dependency
    • Hardening: Prevent direct web access to bootstrap.php
    • Change: In bootstrap, store path to plugin directory in a constant
    • New: Add tests for c2c_parentless_categories()
    • New: Add tests for function invocation filters
    • Change: Tweak some inline comment formatting

2.2.1 (2023-05-20)

  • Change: Note compatibility through WP 6.3+
  • Change: Update copyright date (2023)

2.2 (2021-10-22)

  • Change: Remove long-deprecated functions parentless_categories(), get_parentless_categories_list(), and get_parentless_categories()
  • New: Add DEVELOPER-DOCS.md and move template tag and hooks documentation into it
  • Change: Tweak installation instruction
  • Change: Note compatibility through WP 5.8+
  • Unit tests:
    • Change: Restructure unit test directories
      • Change: Move phpunit/ into tests/phpunit/
      • Change: Move phpunit/bin/ into tests/
    • Change: Remove ‘test-‘ prefix from unit test file
    • Change: In bootstrap, store path to plugin file constant
    • Change: In bootstrap, add backcompat for PHPUnit pre-v6.0

Copyright & Disclaimer

Copyright © 2009-2024 by Scott Reilly (aka coffee2code)

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

Discussion / Support

Have any questions, comments, or suggestions? Please provide them via the plugin’s WordPress.org support forum. I’ll do my best to reply in a timely fashion and help as best I can.

Unfortunately, I cannot provide guaranteed support, nor do I provide support via any other means.

Was this plugin useful useful to you? Consider giving it a rating. If you’re inclined to give it a poor rating, please first post to the support forum to give me a chance to address or explain the situation.