get_page_children( int $page_id, WP_Post[] $pages ): WP_Post[]
- Since
- 1.5.1
- Source
wp-includes/post.php:6248
Description
Descendants are identified from the $pages array passed to the function. No database queries are performed.
Compatibility
- WordPress
- since 1.5.1
- 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
$page_idint- Page ID.
$pagesWP_Post[]- List of page objects from which descendants should be identified.
Return value
WP_Post[]- List of page children.
Performance profile
How much work a call to get_page_children() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Scales with input
- Instructions
- 10–18
- Plugin surface
- None
- Called by
- 1
Touches nothing outside its own arguments.
The body loops, so the work grows with what you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 44.
Nothing here hands control to plugin code.
1 place in core call this, so the cost is paid more often than your own code shows.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost get_page_children() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
!isset($children[$page_id]) | 10–11 | none |
isset($children[$page_id]) | 17–18 | array_reverse() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 44 instructions, 10–18 executed per call, 7 branches. 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.
Used by · 1
- get_pages()Retrieves an array of pages (or hierarchical post type items).
Source code
function get_page_children( $page_id, $pages ) { // Build a hash of ID -> children. $children = array(); foreach ( (array) $pages as $page ) { $children[ (int) $page->post_parent ][] = $page; } $page_list = array(); // Start the search by looking at immediate children. if ( isset( $children[ $page_id ] ) ) { // Always start at the end of the stack in order to preserve original `$pages` order. $to_look = array_reverse( $children[ $page_id ] ); while ( $to_look ) { $p = array_pop( $to_look ); $page_list[] = $p; if ( isset( $children[ $p->ID ] ) ) { foreach ( array_reverse( $children[ $p->ID ] ) as $child ) { // Append to the `$to_look` stack to descend the tree. $to_look[] = $child; } } } } return $page_list;}Changelog
Introduced in 1.5.1. 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 7.0.4 tag, from
src/wp-includes/post.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.