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function is not described

_get_path_to_translation_from_lang_dir() WP 4.7.0

Gets the path to a translation file in the languages directory for the current locale.

Holds a cached list of available .mo files to improve performance.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

String|false. The path to the translation file or false if no translation file was found.

Usage

_get_path_to_translation_from_lang_dir( $domain );
$domain(string) (required)
Text domain. Unique identifier for retrieving translated strings.

Notes

Changelog

Since 4.7.0 Introduced.

Code of _get_path_to_translation_from_lang_dir() WP 5.7.2

<?php
function _get_path_to_translation_from_lang_dir( $domain ) {
	static $cached_mofiles = null;

	if ( null === $cached_mofiles ) {
		$cached_mofiles = array();

		$locations = array(
			WP_LANG_DIR . '/plugins',
			WP_LANG_DIR . '/themes',
		);

		foreach ( $locations as $location ) {
			$mofiles = glob( $location . '/*.mo' );
			if ( $mofiles ) {
				$cached_mofiles = array_merge( $cached_mofiles, $mofiles );
			}
		}
	}

	$locale = determine_locale();
	$mofile = "{$domain}-{$locale}.mo";

	$path = WP_LANG_DIR . '/plugins/' . $mofile;
	if ( in_array( $path, $cached_mofiles, true ) ) {
		return $path;
	}

	$path = WP_LANG_DIR . '/themes/' . $mofile;
	if ( in_array( $path, $cached_mofiles, true ) ) {
		return $path;
	}

	return false;
}