What is the output of the following? “`js const handler = { apply(target, thisArg, args) { return target.apply(thisArg, args) * 2; } }; const double = new Proxy(x => x + 1, handler); console.log(double(5)); “`

Question

JavaScript Professional — Medium

What is the output of the following? “`js const handler = { apply(target, thisArg, args) { return target.apply(thisArg, args) * 2; } }; const double = new Proxy(x => x + 1, handler); console.log(double(5)); “`

Accepted Answer

The output of the code is 12 because the Proxy `double` is created with a handler that multiplies the result of the original function by 2. Therefore, when `double(5)` is called, the original function `(x => x + 1)` returns 6, which is then multiplied by 2.