load_plugin_textdomain( string $domain, string|false $deprecated = false, string|false $plugin_rel_path = false ): bool
- Since
- 1.5.0, 4.6.0, 6.7.0
- Source
wp-includes/l10n.php:999
Description
If the path is not given then it will be the root of the plugin directory.
The .mo file should be named based on the text domain with a dash, and then the locale exactly.
Compatibility
- WordPress
- since 6.7.0
- 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
$domainstring- Unique identifier for retrieving translated strings
$deprecatedstring|falseoptional- Deprecated. Use the $plugin_rel_path parameter instead.
Default false.Default:false $plugin_rel_pathstring|falseoptional- Relative path to WP_PLUGIN_DIR where the .mo file resides.
Default false.Default:false
Return value
bool- True when textdomain is successfully loaded, false otherwise.
Performance profile
How much work a call to load_plugin_textdomain() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 8–30
- Plugin surface
- None
- Called by
- 1
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 37.
Nothing here hands control to plugin code.
1 place in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
do_action()one call below load_plugin_textdomain()
Further down the call graph this can also reach query, option, cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 3 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost load_plugin_textdomain() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
!is_string($domain) | 8 | none |
is_string($domain) | 19–25 | ->set_custom_path() |
is_string($domain) && $plugin_rel_path === false && $deprecated !== false | 26–30 | _deprecated_argument(), ->set_custom_path() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 37 | 8–30 | 5 | |
| 8.5 | 37 | 8–30 | 5 | |
| 8.4 | 37 | 8–30 | 5 | 6 fewer instructions than PHP 8.3 |
| 8.3 | 43 | 8–33 | 5 | |
| 8.2 | 43 | 8–33 | 5 | |
| 8.1 | 43 | 8–33 | 5 | |
| 7.4 | 43 | 8–33 | 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 · 1
- _deprecated_argument()Marks a function argument as deprecated and inform when it has been used.
Used by · 1
- _get_plugin_data_markup_translate()Sanitizes plugin data, optionally adds markup, optionally translates.
Source code
function load_plugin_textdomain( $domain, $deprecated = false, $plugin_rel_path = false ) { /** @var WP_Textdomain_Registry $wp_textdomain_registry */ /** @var array<string, WP_Translations|NOOP_Translations> $l10n */ global $wp_textdomain_registry, $l10n; if ( ! is_string( $domain ) ) { return false; } if ( false !== $plugin_rel_path ) { $path = WP_PLUGIN_DIR . '/' . trim( $plugin_rel_path, '/' ); } elseif ( false !== $deprecated ) { _deprecated_argument( __FUNCTION__, '2.7.0' ); $path = ABSPATH . trim( $deprecated, '/' ); } else { $path = WP_PLUGIN_DIR; } $wp_textdomain_registry->set_custom_path( $domain, $path ); // If just-in-time loading was triggered before, reset the entry so it can be tried again. if ( isset( $l10n[ $domain ] ) && $l10n[ $domain ] instanceof NOOP_Translations ) { unset( $l10n[ $domain ] ); } return true;}Changelog
Introduced in 1.5.0. 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 6.9.7 tag, from
src/wp-includes/l10n.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.