Source

File: wp-includes/l10n.php

function get_translations_for_domain( $domain ) {
	global $l10n;
	if ( isset( $l10n[ $domain ] ) || ( _load_textdomain_just_in_time( $domain ) && isset( $l10n[ $domain ] ) ) ) {
		return $l10n[ $domain ];
	}

	static $noop_translations = null;
	if ( null === $noop_translations ) {
		$noop_translations = new NOOP_Translations;
	}

	return $noop_translations;
}