JS implementation of new

Realization new The operator

1. Create a blank object
2. Modify the prototype of the blank object to the prototype of the constructor
3. this Point to a blank object , And execute the constructor
4. Returns the object

   function Animal(name,age) {
    
        this.name = name;
        this.age = age;
    }
    function _new(constructor,...args) {
    
        let instance = {
    };
        // instance._proto_ = constructor.prototype;  Are four underscores 
        instance.__proto__ = constructor.prototype; 
        let result = constructor.call(instance,...args); 
        return  typeof result === 'object'? result:instance; //  Returns the non empty object returned by the constructor , Otherwise return the created object 
    }
 let a = _new(Animal,'lli','2');
 console.log('a',a)
 console.log(a instanceof Animal); 
 // expected output: true