unregister_taxonomy( string $taxonomy ): true|WP_Error

Description

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$taxonomystring

Taxonomy name.

Return value

true|WP_Error

True on success, WP_Error on failure or if the taxonomy doesn't exist.

Performance profile

How much work a call to unregister_taxonomy() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Trivial

Touches nothing outside its own arguments.

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

14–22

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 38.

Plugin surface

1 hook

Third-party callbacks on 'unregistered_taxonomy' run inside this call, and their cost is not bounded by anything here.

Called by

0

Nothing in core calls this; the cost is only what you spend yourself.

What it touches

• hookthird-party callbacksdo_action()called directly

Further down the call graph this can also reach query, option, cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 3 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost unregister_taxonomy() can have, taken from its control-flow graph on PHP 8.5.

Hooks and filters fired · 1

One hook fires while unregister_taxonomy() runs, in this order:

1. 1
   do_action( unregistered_taxonomy )actionline 632 (+27 into the body)

   Fires after a taxonomy is unregistered.

Uses · 5

• taxonomy_exists()Determines whether the taxonomy name exists.
• __()Retrieves the translation of $text.
• get_taxonomy()Retrieves the taxonomy object of $taxonomy.
• do_action()Calls the callback functions that have been added to an action hook.
• WP_Error::__construct()Initializes the error.

Source code

View on Trac ↗View on GitHub ↗

605function unregister_taxonomy( $taxonomy ) {606	global $wp_taxonomies;607 608	if ( ! taxonomy_exists( $taxonomy ) ) {609		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );610	}611 612	$taxonomy_object = get_taxonomy( $taxonomy );613 614	// Do not allow unregistering internal taxonomies.615	if ( $taxonomy_object->_builtin ) {616		return new WP_Error( 'invalid_taxonomy', __( 'Unregistering a built-in taxonomy is not allowed.' ) );617	}618 619	$taxonomy_object->remove_rewrite_rules();620	$taxonomy_object->remove_hooks();621 622	// Remove the taxonomy.623	unset( $wp_taxonomies[ $taxonomy ] );624 625	/**626	 * Fires after a taxonomy is unregistered.627	 *628	 * @since 4.5.0629	 *630	 * @param string $taxonomy Taxonomy name.631	 */632	do_action( 'unregistered_taxonomy', $taxonomy );633 634	return true;635}

Changelog

Introduced in 4.5.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 7.1.0 tag, from src/wp-includes/taxonomy.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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