Similar to how WordPress 4.6 introduced WP_Post_Type, version 4.7 will introduce a new WP_Taxonomy class. This changes the global $wp_taxonomies to an array of WP_Taxonomy objects.

WP_Taxonomy provides methods to handle rewrite rules and hooksHooks In WordPress theme and development, hooks are functions that can be applied to an action or a Filter in WordPress. Actions are functions performed when a certain event occurs in WordPress. Filters allow you to modify certain functions. Arguments used to hook both filters and actions look the same.. These methods are used internally by register_taxonomy() and unregister_taxonomy(). Each taxonomyTaxonomy A taxonomy is a way to group things together. In WordPress, some common taxonomies are category, link, tag, or post format. https://codex.wordpress.org/Taxonomies#Default_Taxonomies. argument is now a property of WP_Taxonomy.

The following function has been changed to return a WP_Taxonomy object:

• get_taxonomy()

The following hook parameters are now a WP_Taxonomy object:

• The second parameter $taxonomy of xmlrpc_prepare_taxonomy.
• The second parameter $tax of term_search_min_chars.

The following function accepts a WP_Taxonomy object now:

• get_taxonomy_labels()

Just like with WP_Post_Type, introducing such a class makes further improvements much more feasible.

For more background on the change, see #36224.

#4-7, #dev-notes