wp_get_loading_attr_default( string $context ): string|bool

Description

Compatibility

Deprecated in WordPress 6.3.0. Use wp_get_loading_optimization_attributes() instead.

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

Parameters

$contextstring

Context for the element for which the loading attribute value is requested.

Return value

string|bool

The default loading attribute value. Either 'lazy', 'eager', or a boolean false, to indicate that the loading attribute should be skipped.

Performance profile

How much work a call to wp_get_loading_attr_default() 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

10–55

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 62.

Plugin surface

None

Nothing here hands control to plugin code.

Called by

1

1 place in core call this, so the cost is paid more often than your own code shows.

What it touches

• hookthird-party callbacksdo_action()one call below wp_get_loading_attr_default()

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 · 25 distinct outcomes

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

Uses · 8

• _deprecated_function()Marks a function as deprecated and inform when it has been used.
• doing_filter()Returns whether or not a filter hook is currently being processed.
• did_action()Retrieves the number of times an action has been fired during the current request.
• is_admin()Determines whether the current request is for an administrative interface page.
• in_the_loop()Determines whether the caller is in the Loop.
• is_main_query()Determines whether the query is the main query.
• wp_increase_content_media_count()Increases an internal content media count variable.
• wp_omit_loading_attr_threshold()Gets the threshold for how many of the first content media elements to not lazy-load.

Used by · 1

• wp_img_tag_add_loading_attr()Adds `loading` attribute to an `img` HTML tag.

Source code

View on Trac ↗View on GitHub ↗

4704function wp_get_loading_attr_default( $context ) {4705	_deprecated_function( __FUNCTION__, '6.3.0', 'wp_get_loading_optimization_attributes()' );4706	global $wp_query;4707 4708	// Skip lazy-loading for the overall block template, as it is handled more granularly.4709	if ( 'template' === $context ) {4710		return false;4711	}4712 4713	/*4714	 * Do not lazy-load images in the header block template part, as they are likely above the fold.4715	 * For classic themes, this is handled in the condition below using the 'get_header' action.4716	 */4717	$header_area = WP_TEMPLATE_PART_AREA_HEADER;4718	if ( "template_part_{$header_area}" === $context ) {4719		return false;4720	}4721 4722	// Special handling for programmatically created image tags.4723	if ( 'the_post_thumbnail' === $context || 'wp_get_attachment_image' === $context ) {4724		/*4725		 * Skip programmatically created images within post content as they need to be handled together with the other4726		 * images within the post content.4727		 * Without this clause, they would already be counted below which skews the number and can result in the first4728		 * post content image being lazy-loaded only because there are images elsewhere in the post content.4729		 */4730		if ( doing_filter( 'the_content' ) ) {4731			return false;4732		}4733 4734		// Conditionally skip lazy-loading on images before the loop.4735		if (4736			// Only apply for main query but before the loop.4737			$wp_query->before_loop && $wp_query->is_main_query()4738			/*4739			 * Any image before the loop, but after the header has started should not be lazy-loaded,4740			 * except when the footer has already started which can happen when the current template4741			 * does not include any loop.4742			 */4743			&& did_action( 'get_header' ) && ! did_action( 'get_footer' )4744		) {4745			return false;4746		}4747	}4748 4749	/*4750	 * The first elements in 'the_content' or 'the_post_thumbnail' should not be lazy-loaded,4751	 * as they are likely above the fold.4752	 */4753	if ( 'the_content' === $context || 'the_post_thumbnail' === $context ) {4754		// Only elements within the main query loop have special handling.4755		if ( is_admin() || ! in_the_loop() || ! is_main_query() ) {4756			return 'lazy';4757		}4758 4759		// Increase the counter since this is a main query content element.4760		$content_media_count = wp_increase_content_media_count();4761 4762		// If the count so far is below the threshold, return `false` so that the `loading` attribute is omitted.4763		if ( $content_media_count <= wp_omit_loading_attr_threshold() ) {4764			return false;4765		}4766 4767		// For elements after the threshold, lazy-load them as usual.4768		return 'lazy';4769	}4770 4771	// Lazy-load by default for any unknown context.4772	return 'lazy';4773}

Changelog

Introduced in 5.9.0. 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 6.9.7 tag, from src/wp-includes/deprecated.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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