restore_previous_locale(): string|false
- Since
- 4.7.0
- Source
wp-includes/l10n.php:1876
Compatibility
- WordPress
- since 4.7.0
- 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.
Return value
string|false- Locale on success, false on error.
Performance profile
How much work a call to restore_previous_locale() 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
- 3–5
- Plugin surface
- None
- Called by
- 24
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 6.
Nothing here hands control to plugin code.
24 places in core call this, so the cost is paid more often than your own code shows.
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 restore_previous_locale() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 3 | none |
| always | 5 | ->restore_previous_locale() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 6 instructions, 3–5 executed per call, 1 branch. 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.
Used by · 24
- WP_Automatic_Updater::send_debug_email()Prepares and sends an email of a full log of background update results, useful for debugging and geekery.
- WP_Automatic_Updater::send_email()Sends an email upon the completion or failure of a background core update.
- WP_Automatic_Updater::send_plugin_theme_email()Sends an email upon the completion or failure of a plugin or theme background update.
- WP_Customize_Manager::customize_preview_settings()Prints JavaScript settings for preview frame.
- WP_Customize_Selective_Refresh::export_preview_data()Exports data in preview after it has finished rendering so that partials can be added at runtime.
- WP_Customize_Widgets::export_preview_data()Communicates the sidebars that appeared on the page at the very end of the page, and at the very end of the wp_footer,
- WP_Recovery_Mode_Email_Service::send_recovery_mode_email()Sends the Recovery Mode email to the site admin email address.
- _wp_privacy_send_erasure_fulfillment_notification()Notifies the user when their erasure request is fulfilled.
- insert_with_markers()Inserts an array of strings into a file (.htaccess), placing it between BEGIN and END markers.
- retrieve_password()Handles sending a password retrieval email to a user.
- update_network_option_new_admin_email()Sends a confirmation request email when a change of network admin email address is attempted.
- update_option_new_admin_email()Sends a confirmation request email when a change of site admin email address is attempted.
Show all 24
- wp_new_user_notification()Emails login credentials to a newly-registered user.
- wp_notify_moderator()Notifies the moderator of the site about a new comment that is awaiting approval.
- wp_notify_postauthor()Notifies an author (and/or others) of a comment/trackback/pingback on a post.
- wp_password_change_notification()Notifies the blog admin of a user changing password, normally via email.
- wp_privacy_send_personal_data_export_email()Send an email to the user with a link to the personal data export file
- wp_send_user_request()Send a confirmation request email to confirm an action.
- wp_update_user()Updates a user in the database.
- wpmu_new_site_admin_notification()Notifies the Multisite network administrator that a new site was created.
- wpmu_signup_blog_notification()Sends a confirmation request email to a user when they sign up for a new site. The new site will not become active until the confirmation link is clicked.
- wpmu_signup_user_notification()Sends a confirmation request email to a user when they sign up for a new user account (without signing up for a site at the same time). The user account will not become active until the confirmation link is clicked.
- wpmu_welcome_notification()Notifies the site administrator that their site activation was successful.
- wpmu_welcome_user_notification()Notifies a user that their account activation has been successful.
Source code
function restore_previous_locale() { /* @var WP_Locale_Switcher $wp_locale_switcher */ global $wp_locale_switcher; if ( ! $wp_locale_switcher ) { return false; } return $wp_locale_switcher->restore_previous_locale();}Changelog
Introduced in 4.7.0. 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.