Question

The snippet that filters the filtered set is __________

(a) var t=new FilteredSet(s, {function(s) {return !(x instanceof Set);});

(b) var t=new FilteredSet{function(s) {return !(x instanceof Set);});

(c) var t=new FilteredSet(s, {function(s) {return (x instanceof Set);});

(d) var t=new FilteredSet(s, {function(s) {return x;});

The question was asked in an interview for internship.

I'd like to ask this question from Classes in JavaScript topic in division Classes and Modules in JavaScript of JavaScript

Answer 1

The correct answer is (a) var t=new FilteredSet(s, {function(s) {return !(x instanceof Set);});

Best explanation: The instanceof operator is used to check the type of an object at run time. The instanceof operator returns a boolean value that indicates if an object is an instance of a particular class.