is_protected_meta( string $meta_key, string $meta_type = '' ): bool
- Since
- 3.1.3
- Source
wp-includes/meta.php:1312
Compatibility
- WordPress
- since 3.1.3
- 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
$meta_keystring- Metadata key.
$meta_typestringoptional- Type of object metadata is for. Accepts 'blog', 'post', 'comment', 'term', 'user', or any other object type with an associated meta table. Default empty string.Default:
''
Return value
bool- Whether the meta key is considered protected.
Performance profile
How much work a call to is_protected_meta() 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
- 15–17
- Plugin surface
- 1 hook
- Called by
- 11
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.
Third-party callbacks on 'is_protected_meta' run inside this call, and their cost is not bounded by anything here.
11 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
apply_filters()called directly
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 is_protected_meta() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 15–17 | apply_filters() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 17 | 15–17 | 1 | |
| 8.5 | 17 | 15–17 | 1 | |
| 8.4 | 17 | 15–17 | 1 | 4 fewer instructions than PHP 8.3 |
| 8.3 | 21 | 19–21 | 1 | |
| 8.2 | 21 | 19–21 | 1 | |
| 8.1 | 21 | 19–21 | 1 | |
| 7.4 | 21 | 19–21 | 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.
Hooks and filters fired · 1
One hook fires while is_protected_meta() runs, in this order:
- apply_filters( is_protected_meta )filterline 1326 (+14 into the body)
Filters whether a meta key is considered protected.
Uses · 1
- apply_filters()Calls the callback functions that have been added to a filter hook.
Used by · 11
- _block_bindings_post_meta_get_value()Gets value for Post Meta source.
- _list_meta_row()Outputs a single row of public meta data in the Custom Fields meta box.
- add_meta()Adds post meta data defined in the `$_POST` superglobal for a post with given ID.
- edit_post()Updates an existing post with values provided in `$_POST`.
- map_meta_cap()Maps a capability to the primitive capabilities required of the given user to satisfy the capability being checked.
- meta_form()Prints the form in the Custom Fields meta box.
- post_custom_meta_box()Displays custom fields form fields.
- register_meta()Registers a meta key.
- the_meta()Displays a list of post custom fields.
- wp_ajax_add_meta()Handles adding meta via AJAX.
- wp_ajax_delete_meta()Handles deleting meta via AJAX.
Source code
function is_protected_meta( $meta_key, $meta_type = '' ) { $sanitized_key = preg_replace( "/[^\x20-\x7E\p{L}]/", '', $meta_key ); $protected = strlen( $sanitized_key ) > 0 && ( '_' === $sanitized_key[0] ); /** * Filters whether a meta key is considered protected. * * @since 3.2.0 * * @param bool $protected Whether the key is considered protected. * @param string $meta_key Metadata key. * @param string $meta_type Type of object metadata is for. Accepts 'blog', 'post', 'comment', 'term', * 'user', or any other object type with an associated meta table. */ return apply_filters( 'is_protected_meta', $protected, $meta_key, $meta_type );}Changelog
Introduced in 3.1.3. 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/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.