The use of wrapper objects for primitive types is gratuitous, confusing and dangerous. If you use a wrapper object constructor for type conversion,
just remove the new keyword, and you'll get a primitive value automatically. If you use a wrapper object as a way to add properties to a
primitive, you should re-think the design. Such uses are considered bad practice, and should be refactored.
let x = new Number("0");
if (x) {
alert('hi'); // Shows 'hi'.
}
let x = Number("0");
if (x) {
alert('hi');
}
Cases when argument of primitive type constructor is a literal of the same type are ignored, except new Boolean(false).
let booleanObject = new Boolean(true);
let numberObject = new Number(0);
let stringObject = new String('');