wp_unique_id_from_values( array $data, string $prefix = '' ): string
- Since
- 6.8.0
- Source
wp-includes/functions.php:8208
Description
This function serializes the array into a JSON string and generates a hash that serves as a unique identifier. Optionally, a prefix can be added to the generated ID for context or categorization.
Compatibility
- WordPress
- since 6.8.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in 4 of the 5 tracked releases, added in 6.8.0, and compiles on PHP 7.4 through 8.6-dev.
Parameters
$dataarray- The input array to generate an ID from.
$prefixstringoptional- A prefix to prepend to the generated ID. Default empty string.Default:
''
Return value
string- The generated unique ID for the array.
Performance profile
How much work a call to wp_unique_id_from_values() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 15–27
- Plugin surface
- None
- Called by
- 2
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 27.
Nothing here hands control to plugin code.
2 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
do_action()one call below wp_unique_id_from_values()
Further down the call graph this can also reach option, query, cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_unique_id_from_values() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
!empty($data) | 15 | wp_json_encode(), md5() |
empty($data) | 27 | __(), sprintf(), _doing_it_wrong(), wp_json_encode(), md5() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 27 | 15–27 | 1 | |
| 8.5 | 27 | 15–27 | 1 | |
| 8.4 | 27 | 15–27 | 1 | 4 fewer instructions than PHP 8.3 |
| 8.3 | 31 | 19–31 | 1 | |
| 8.2 | 31 | 19–31 | 1 | |
| 8.1 | 31 | 19–31 | 1 | |
| 7.4 | 31 | 19–31 | 1 |
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 · 3
- _doing_it_wrong()Marks something as being incorrectly called.
- __()Retrieves the translation of $text.
- wp_json_encode()Encodes a variable into JSON, with some confidence checks.
Used by · 2
- wp_render_custom_css_support_styles()Render the custom CSS stylesheet and add class name to block as required.
- wp_render_layout_support_flag()Renders the layout config to the block wrapper.
Source code
function wp_unique_id_from_values( array $data, string $prefix = '' ): string { if ( empty( $data ) ) { _doing_it_wrong( __FUNCTION__, sprintf( /* translators: %s: The parameter name. */ __( 'The %s parameter must not be empty.' ), '$data' ), '6.8.0' ); } $serialized = wp_json_encode( $data ); $hash = substr( md5( $serialized ), 0, 8 ); return $prefix . $hash;}Changelog
Introduced in 6.8.0. Unchanged from 6.8.8 through 7.1.0.
Signature, return type and hooks compared across 4 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.