Gettext_Translations

254	class Gettext_Translations extends Translations {255 256		/**257		 * Number of plural forms.258		 *259		 * @var int260		 *261		 * @since 2.8.0262		 */263		public $_nplurals;264 265		/**266		 * Callback to retrieve the plural form.267		 *268		 * @var callable269		 *270		 * @since 2.8.0271		 */272		public $_gettext_select_plural_form;273 274		/**275		 * The gettext implementation of select_plural_form.276		 *277		 * It lives in this class, because there are more than one descendant, which will use it and278		 * they can't share it effectively.279		 *280		 * @since 2.8.0281		 *282		 * @param int $count Plural forms count.283		 * @return int Plural form to use.284		 */285		public function gettext_select_plural_form( $count ) {286			if ( ! isset( $this->_gettext_select_plural_form ) || is_null( $this->_gettext_select_plural_form ) ) {287				list( $nplurals, $expression )     = $this->nplurals_and_expression_from_header( $this->get_header( 'Plural-Forms' ) );288				$this->_nplurals                   = $nplurals;289				$this->_gettext_select_plural_form = $this->make_plural_form_function( $nplurals, $expression );290			}291			return call_user_func( $this->_gettext_select_plural_form, $count );292		}293 294		/**295		 * Returns the nplurals and plural forms expression from the Plural-Forms header.296		 *297		 * @since 2.8.0298		 *299		 * @param string $header300		 * @return array{0: int, 1: string}301		 */302		public function nplurals_and_expression_from_header( $header ) {303			if ( preg_match( '/^\s*nplurals\s*=\s*(\d+)\s*;\s+plural\s*=\s*(.+)$/', $header, $matches ) ) {304				$nplurals   = (int) $matches[1];305				$expression = trim( $matches[2] );306				return array( $nplurals, $expression );307			} else {308				return array( 2, 'n != 1' );309			}310		}311 312		/**313		 * Makes a function, which will return the right translation index, according to the314		 * plural forms header.315		 *316		 * @since 2.8.0317		 *318		 * @param int    $nplurals319		 * @param string $expression320		 * @return callable321		 */322		public function make_plural_form_function( $nplurals, $expression ) {323			try {324				$handler = new Plural_Forms( rtrim( $expression, ';' ) );325				return array( $handler, 'get' );326			} catch ( Exception $e ) {327				// Fall back to default plural-form function.328				return $this->make_plural_form_function( 2, 'n != 1' );329			}330		}331 332		/**333		 * Adds parentheses to the inner parts of ternary operators in