wp_find_hierarchy_loop( callable $callback, int $start, int $start_parent, array $callback_args = array() ): array
- Since
- 3.1.0
- Source
wp-includes/functions.php:7211
Compatibility
- WordPress
- since 3.1.0
- 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
$callbackcallable- Function that accepts ( ID, $callback_args ) and outputs parent_ID.
$startint- The ID to start the loop check at.
$start_parentint- The parent_ID of $start to use instead of calling $callback( $start ).
Use null to always use $callback. $callback_argsarrayoptional- Additional arguments to send to $callback. Default empty array.Default:
array()
Return value
array- IDs of all members of loop.
Performance profile
How much work a call to wp_find_hierarchy_loop() 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
- 17–25
- Plugin surface
- None
- Called by
- 2
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 27.
Nothing here hands control to plugin code.
2 places 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 wp_find_hierarchy_loop() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 17–18 | wp_find_hierarchy_loop_tortoise_hare() |
| always | 24–25 | wp_find_hierarchy_loop_tortoise_hare(), wp_find_hierarchy_loop_tortoise_hare() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 27 | 17–25 | 2 | |
| 8.5 | 27 | 17–25 | 2 | |
| 8.4 | 27 | 17–25 | 2 | |
| 8.3 | 27 | 17–25 | 2 | |
| 8.2 | 27 | 17–25 | 2 | |
| 8.1 | 27 | 17–25 | 2 | 1 fewer instruction than PHP 7.4 |
| 7.4 | 28 | 18–25 | 2 |
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 · 1
- wp_find_hierarchy_loop_tortoise_hare()Uses the "The Tortoise and the Hare" algorithm to detect loops.
Used by · 2
- wp_check_post_hierarchy_for_loops()Checks the given subset of the post hierarchy for hierarchy loops.
- wp_check_term_hierarchy_for_loops()Checks the given subset of the term hierarchy for hierarchy loops.
Source code
function wp_find_hierarchy_loop( $callback, $start, $start_parent, $callback_args = array() ) { $override = is_null( $start_parent ) ? array() : array( $start => $start_parent ); $arbitrary_loop_member = wp_find_hierarchy_loop_tortoise_hare( $callback, $start, $override, $callback_args ); if ( ! $arbitrary_loop_member ) { return array(); } return wp_find_hierarchy_loop_tortoise_hare( $callback, $arbitrary_loop_member, $override, $callback_args, true );}Changelog
Introduced in 3.1.0. 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/functions.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.