code: function add( key, value ) {
  		var desc;
  		switch ( typeof value ) {
  			case 'object'   : desc = util.type( value ) == 'descriptor' ? value : util.describe( { value : value }, 'cw' );          break;
  			case 'function' : desc = util.describe( make_method( 'parent', value, get_method_descriptor( this, key ), key ), 'cw' ); break;
  			default         : desc = util.describe( value, 'cew' );
  		}
  		util.def( this, key, desc, true );
  		return this.constructor;
  	}
docs: Class construction methods