WP_Object_Cache::is_valid_key( int|string $key ): bool
- Since
- 6.1.0
- Source
wp-includes/class-wp-object-cache.php:140
Compatibility
- WordPress
- since 6.1.0
- 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
$keyint|string- Cache key to check for validity.
Return value
bool- Whether the key is valid.
Performance profile
How much work a call to WP_Object_Cache::is_valid_key() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 4–41
- Plugin surface
- None
- Called by
- 7
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 48.
Nothing here hands control to plugin code.
7 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
do_action()one call below WP_Object_Cache::is_valid_key()
Further down the call graph this can also reach query, option, cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 5 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_Object_Cache::is_valid_key() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 4–9 | none |
!is_int($key) && function_exists() && is_string($key) | 33–36 | function_exists(), __(), debug_backtrace(), _doing_it_wrong() |
!is_int($key) && !function_exists() && is_string($key) | 35–38 | function_exists(), wp_load_translations_early(), __(), debug_backtrace(), _doing_it_wrong() |
!is_int($key) && !is_string($key) && function_exists() | 36–39 | function_exists(), __(), sprintf(), debug_backtrace(), _doing_it_wrong() |
!is_int($key) && !is_string($key) && !function_exists() | 38–41 | function_exists(), wp_load_translations_early(), __(), sprintf(), debug_backtrace(), _doing_it_wrong() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 46 | 4–40 | 5 | 2 fewer instructions than PHP 8.5 |
| 8.5 | 48 | 4–41 | 5 | |
| 8.4 | 48 | 4–41 | 5 | 4 fewer instructions than PHP 8.3 |
| 8.3 | 52 | 4–45 | 5 | |
| 8.2 | 52 | 4–45 | 5 | |
| 8.1 | 52 | 4–45 | 5 | |
| 7.4 | 52 | 4–45 | 5 |
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
- wp_load_translations_early()Attempts an early load of translations.
- __()Retrieves the translation of $text.
- _doing_it_wrong()Marks something as being incorrectly called.
Used by · 7
- WP_Object_Cache::add()Adds data to the cache if it doesn't already exist.
- WP_Object_Cache::decr()Decrements numeric cache item's value.
- WP_Object_Cache::delete()Removes the contents of the cache key in the group.
- WP_Object_Cache::get()Retrieves the cache contents, if it exists.
- WP_Object_Cache::incr()Increments numeric cache item's value.
- WP_Object_Cache::replace()Replaces the contents in the cache, if contents already exist.
- WP_Object_Cache::set()Sets the data contents into the cache.
Source code
protected function is_valid_key( $key ) { if ( is_int( $key ) ) { return true; } if ( is_string( $key ) && trim( $key ) !== '' ) { return true; } $type = gettype( $key ); if ( ! function_exists( '__' ) ) { wp_load_translations_early(); } $message = is_string( $key ) ? __( 'Cache key must not be an empty string.' ) /* translators: %s: The type of the given cache key. */ : sprintf( __( 'Cache key must be an integer or a non-empty string, %s given.' ), $type ); _doing_it_wrong( sprintf( '%s::%s', __CLASS__, debug_backtrace( DEBUG_BACKTRACE_IGNORE_ARGS, 2 )[1]['function'] ), $message, '6.1.0' ); return false; }Changelog
Introduced in 6.1.0. 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/class-wp-object-cache.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.