_load_textdomain_just_in_time( string $domain ): bool

1349function _load_textdomain_just_in_time( $domain ) {1350	/** @var WP_Textdomain_Registry $wp_textdomain_registry */1351	global $l10n_unloaded, $wp_textdomain_registry;1352 1353	$l10n_unloaded = (array) $l10n_unloaded;1354 1355	// Short-circuit if domain is 'default' which is reserved for core.1356	if ( 'default' === $domain || isset( $l10n_unloaded[ $domain ] ) ) {1357		return false;1358	}1359 1360	if ( ! $wp_textdomain_registry->has( $domain ) ) {1361		return false;1362	}1363 1364	$locale = determine_locale();1365	$path   = $wp_textdomain_registry->get( $domain, $locale );1366	if ( ! $path ) {1367		return false;1368	}1369 1370	if ( ! doing_action( 'after_setup_theme' ) && ! did_action( 'after_setup_theme' ) ) {1371		_doing_it_wrong(1372			__FUNCTION__,1373			sprintf(1374				/* translators: 1: The text domain. 2: 'init'. */1375				__( 'Translation loading for the %1$s domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the %2$s action or later.' ),1376				'<code>' . $domain . '</code>',1377				'<code>init</code>'1378			),1379			'6.7.0'1380		);1381	}1382 1383	// Themes with their language directory outside of WP_LANG_DIR have a different file name.1384	$template_directory   = trailingslashit( get_template_directory() );1385	$stylesheet_directory = trailingslashit( get_stylesheet_directory() );1386	if ( str_starts_with( $path, $template_directory ) || str_starts_with( $path, $stylesheet_directory ) ) {1387		$mofile = "{$path}{$locale}.mo";1388	} else {1389		$mofile = "{$path}{$domain}-{$locale}.mo";1390	}1391 1392	return load_textdomain( $domain, $mofile, $locale );1393}