import 'core-js/es6/symbol' ; declare global { interface ObjectConstructor { byString ( obj , key ) : any ; } } if ( ! Object . byString ) { Object . byString = function ( o , s ) { try { s = s . replace ( /\[(\w+)\]/g , '.$1' ) ; s = s . replace ( /^\./ , '' ) ; var a = s . split ( '.' ) ; for ( var i = 0 , n = a . length ; i < n ; ++ i ) { var k = a [ i ] ; if ( k in o ) { o = o [ k ] ; } else { return ; } } return o ; } catch ( e ) { return null ; } } ; }