is_attachment( int|string|int[]|string[] $attachment = '' ): bool
- Since
- 2.0.0
- Source
wp-includes/query.php:213
Description
For more information on this and similar theme functions, check out the https://developer.wordpress.org/themes/basics/conditional-tags/ Conditional Tags article in the Theme Developer Handbook.
Compatibility
- WordPress
- since 2.0.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$attachmentint|string|int[]|string[]optional- Attachment ID, title, slug, or array of such to check against. Default empty.Default:
''
Return value
bool- Whether the query is for an existing attachment page.
Performance profile
How much work a call to is_attachment() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 8–13
- Plugin surface
- None
- Called by
- 26
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 17.
Nothing here hands control to plugin code.
26 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
do_action()one call below is_attachment()
Further down the call graph this can also reach query, option, cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost is_attachment() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
isset($wp_query) | 8 | ->is_attachment() |
!isset($wp_query) | 13 | __(), _doing_it_wrong() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 17 instructions, 8–13 executed per call, 1 branch. The work does not change between versions.
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Uses · 2
- _doing_it_wrong()Marks something as being incorrectly called.
- __()Retrieves the translation of $text.
Used by · 26
- adjacent_posts_rel_link_wp_head()Displays relational links for the posts adjacent to the current post for single post pages.
- get_adjacent_post_link()Retrieves the adjacent post link.
- get_adjacent_post_rel_link()Retrieves the adjacent post relational link.
- get_body_class()Retrieves an array of the class names for the body element.
- get_boundary_post()Retrieves the boundary post.
- get_post_class()Retrieves an array of the class names for the post container element.
- redirect_canonical()Redirects incoming links to the proper URL based on the site url.
- twenty_twenty_one_can_show_post_thumbnail()Determines if post thumbnail can be displayed.
- twentyeleven_custom_excerpt_more()Adds a pretty "Continue Reading" link to custom post excerpts.
- twentyfifteen_entry_meta()Prints HTML with meta information for the categories, tags.
- twentyfifteen_post_nav_background()Adds featured image as background image to post navigation elements.
- twentyfifteen_post_thumbnail()Displays an optional post thumbnail.
Show all 26
- twentyfourteen_body_classes()Extends the default WordPress body classes.
- twentyfourteen_content_width()Adjusts content_width value for image attachment template.
- twentyfourteen_post_classes()Extends the default WordPress post classes.
- twentyfourteen_post_nav()Displays navigation to next/previous post when applicable.
- twentyfourteen_post_thumbnail()Displays an optional post thumbnail.
- twentynineteen_can_show_post_thumbnail()Determines if post thumbnail can be displayed.
- twentysixteen_post_thumbnail()Displays an optional post thumbnail.
- twentyten_custom_excerpt_more()Adds a pretty "Continue Reading" link to custom post excerpts.
- twentythirteen_body_class()Extends the default WordPress body classes.
- twentythirteen_content_width()Adjusts content_width value for video post formats and attachment templates.
- twentythirteen_post_nav()Displays navigation to next/previous post when applicable.
- twentytwelve_content_width()Adjusts content width in certain contexts.
- wp_embed_excerpt_attachment()Filters the post excerpt for the embed template.
- wp_list_pages()Retrieves or displays a list of pages (or hierarchical post type items) in list (li) format.
Source code
function is_attachment( $attachment = '' ) { global $wp_query; if ( ! isset( $wp_query ) ) { _doing_it_wrong( __FUNCTION__, __( 'Conditional query tags do not work before the query is run. Before then, they always return false.' ), '3.1.0' ); return false; } return $wp_query->is_attachment( $attachment );}Changelog
Introduced in 2.0.0. Unchanged from 6.7.7 through 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/query.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.