wppaste
WordPress

registered_meta_key_exists( string $object_type, string $meta_key, string $object_subtype = '' ): bool

Since
4.6.0, 4.9.8
Source
wp-includes/meta.php:1641
Checks if a meta key is registered.

Compatibility

WordPress
since 4.9.8
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

$object_typestring
Type of object metadata is for. Accepts 'blog', 'post', 'comment', 'term', 'user', or any other object type with an associated meta table.
$meta_keystring
Metadata key.
$object_subtypestringoptional
The subtype of the object type. Default empty string.Default: ''

Return value

bool
True if the meta key is registered to the object type and, if provided, the object subtype. False if not.

Performance profile

How much work a call to registered_meta_key_exists() 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

Executed per call on PHP 8.5. The body compiles to 10.

Plugin surface
None

Nothing here hands control to plugin code.

Called by
2

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

What one call costs · 1 distinct outcome

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

WhenInstructionsCalls it makes
always10get_registered_meta_keys()

Across PHP versions

Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 10 instructions, 10 executed per call, 0 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.

Uses · 1

Used by · 2

Source code

View on Trac View on GitHub 

function registered_meta_key_exists( $object_type, $meta_key, $object_subtype = '' ) {	$meta_keys = get_registered_meta_keys( $object_type, $object_subtype ); 	return isset( $meta_keys[ $meta_key ] );}

Changelog

Introduced in 4.6.0. 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.

4.9.8
The $object_subtype parameter was added.from the docblock
4.6.0
Introduced.from the docblock

About this page

Parsed data
Generated from the wordpress-develop 7.1.0 tag, from src/wp-includes/meta.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.