wp_trim_excerpt( string $text = '', WP_Post|object|int $post = null ): string

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

$textstringoptional

The excerpt. If set to empty, an excerpt is generated.Default: ''

$postWP_Post|object|intoptional

WP_Post instance or Post ID/object. Default null.Default: null

Return value

string

The excerpt.

Performance profile

How much work a call to wp_trim_excerpt() 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

Heavy

Reaches the database via get_post().

Scaling

Constant

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

Instructions

18

Executed per call on PHP 8.5. The body compiles to 106.

Plugin surface

4 hooks

Third-party callbacks on 'the_content', 'excerpt_length', 'excerpt_more' 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

• querycontent queryget_post()called directly
• hookthird-party callbacksapply_filters()called directly
• optionoption read or writeget_option()one call below wp_trim_excerpt()

Further down the call graph this can also reach 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 · 1 distinct outcome

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

Hooks and filters fired · 4

4 hooks fire while wp_trim_excerpt() runs, in this order:

1. 1
   apply_filters( the_content )filterline 3965 (+25 into the body)

   Filters the post content.

2. 2
   apply_filters( excerpt_length )filterline 3992 (+52 into the body)

   Filters the maximum number of words in a post excerpt.

3. 3
   apply_filters( excerpt_more )filterline 4001 (+61 into the body)

   Filters the string in the "more" link displayed after a trimmed excerpt.

4. 4
   apply_filters( wp_trim_excerpt )filterline 4014 (+74 into the body)

   Filters the trimmed excerpt string.

Uses · 10

• get_post()Retrieves post data given a post ID or post object.
• get_the_content()Retrieves the post content.
• strip_shortcodes()Removes all shortcode tags from the given content.
• excerpt_remove_blocks()Parses blocks out of a content string, and renders those appropriate for the excerpt.
• excerpt_remove_footnotes()Parses footnotes markup out of a content string, and renders those appropriate for the excerpt.
• remove_filter()Removes a callback function from a filter hook.
• apply_filters()Calls the callback functions that have been added to a filter hook.
• add_filter()Adds a callback function to a filter hook.
• _x()Retrieves translated string with gettext context.
• wp_trim_words()Trims text to a certain number of words.

Source code

View on Trac ↗View on GitHub ↗

3940function wp_trim_excerpt( $text = '', $post = null ) {3941	$raw_excerpt = $text;3942 3943	if ( '' === trim( $text ) ) {3944		$post = get_post( $post );3945		$text = get_the_content( '', false, $post );3946 3947		$text = strip_shortcodes( $text );3948		$text = excerpt_remove_blocks( $text );3949		$text = excerpt_remove_footnotes( $text );3950 3951		/*3952		 * Temporarily unhook wp_filter_content_tags() since any tags3953		 * within the excerpt are stripped out. Modifying the tags here3954		 * is wasteful and can lead to bugs in the image counting logic.3955		 */3956		$filter_image_removed = remove_filter( 'the_content', 'wp_filter_content_tags', 12 );3957 3958		/*3959		 * Temporarily unhook do_blocks() since excerpt_remove_blocks( $text )3960		 * handles block rendering needed for excerpt.3961		 */3962		$filter_block_removed = remove_filter( 'the_content', 'do_blocks', 9 );3963 3964		/** This filter is documented in wp-includes/post-template.php */3965		$text = apply_filters( 'the_content', $text );3966		$text = str_replace( ']]>', ']]>', $text );3967 3968		// Restore the original filter if removed.3969		if ( $filter_block_removed ) {3970			add_filter( 'the_content', 'do_blocks', 9 );3971		}3972 3973		/*3974		 * Only restore the filter callback if it was removed above. The logic3975		 * to unhook and restore only applies on the default priority of 10,3976		 * which is generally used for the filter callback in WordPress core.3977		 */3978		if ( $filter_image_removed ) {3979			add_filter( 'the_content', 'wp_filter_content_tags', 12 );3980		}3981 3982		/* translators: Maximum number of words used in a post excerpt. */3983		$excerpt_length = (int) _x( '55', 'excerpt_length' );3984 3985		/**3986		 * Filters the maximum number of words in a post excerpt.3987		 *3988		 * @since 2.7.03989		 *3990		 * @param int $number The maximum number of words. Default 55.3991		 */3992		$excerpt_length = (int) apply_filters( 'excerpt_length', $excerpt_length );3993 3994		/**3995		 * Filters the string in the "more" link displayed after a trimmed excerpt.3996		 *3997		 * @since 2.9.03998		 *3999		 * @param string $more_string The string shown within the more link.4000		 */4001		$excerpt_more = apply_filters( 'excerpt_more', ' ' . '[…]' );4002		$text         = wp_trim_words( $text, $excerpt_length, $excerpt_more );4003 4004	}4005 4006	/**4007	 * Filters the trimmed excerpt string.4008	 *4009	 * @since 2.8.04010	 *4011	 * @param string $text        The trimmed text.4012	 * @param string $raw_excerpt The text prior to trimming.4013	 */4014	return apply_filters( 'wp_trim_excerpt', $text, $raw_excerpt );4015}

Changelog

Introduced in 1.5.0. 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 6.7.7 tag, from src/wp-includes/formatting.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

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