It is not possible to assign only the property name 'object name' [object object] '

Question

The following code throws an error only for the property name. This can be fixed by specifying the property nameas being written to the arguments Object.create, but I'm trying to understand why this is happening (and there may be a more elegant way to fix it).

var BaseClass = function (data) {
  Object.assign(this, data);
}

var ExtendedClass = function () {
  BaseClass.apply(this, arguments);
}

ExtendedClass.prototype = Object.create(BaseClass);

console.log(new ExtendedClass({ type: 'foo' }));
new ExtendedClass({ name: 'foo' });

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Answer 1

You cannot change a property of a namefunction. The descriptor says this is not writable...

var BaseClass = function (data) {
  Object.assign(this, data);
};

console.log(Object.getOwnPropertyDescriptor(BaseClass, 'name'));

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But since this configurable, you can use Object.defineProperty().

var BaseClass = function (data) {
  Object.assign(this, data);
};

Object.defineProperty(BaseClass, 'name', {
  writable: true,
  value: 'Foo'
});

console.log(BaseClass.name);

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---

EDIT

! ... , , . , ES5 .

ExtendedClass.prototype = Object.create(BaseClass); - , . , ExtendedClass . , , .

function BaseClass(data) {
  console.log(this instanceof BaseClass); // "this" is not an instance of "BaseClass"
  console.log(this instanceof Function); // "this" is a function
  console.log(this.name); // "this" is "BaseClass"
  
  Object.assign(this, data);
}

function ExtendedClass() {
  BaseClass.apply(this, arguments);
}
ExtendedClass.prototype = Object.create(BaseClass);

new ExtendedClass({ type: 'foo' });

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this BaseClass. ...

, JavaScript :

ExtendedClass.prototype = Object.create(BaseClass.prototype);
ExtendedClass.prototype.constructor = ExtendedClass;

:

function BaseClass(data) {
  console.log(this instanceof BaseClass); // "this" is an instance of "BaseClass"
  console.log(this instanceof Function); // "this" is not a function
  console.log(this.name); // "this" has no name yet
  
  Object.assign(this, data);
}

function ExtendedClass() {
  BaseClass.apply(this, arguments);
}
ExtendedClass.prototype = Object.create(BaseClass.prototype);
ExtendedClass.prototype.constructor = ExtendedClass;

var instance = new ExtendedClass({ name: 'foo' });

console.log(instance.name); // foo
console.log(BaseClass.name); // BaseClass
console.log(ExtendedClass.name); // ExtendedClass

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Answer 2

name Function, . .

name MDN.

Answer 3

Angular + TypeScript:

WRONG/INVALID:

@Output any_var = new EventEmitter();

GOOD/CORRECT:

@Output() any_var = new EventEmitter();

Answer 4

Angular + Typescript + NgRX:

, , , .

let x = [...y];

Redux/NgRX, , , . , .

let x = JSON.parse(JSON.stringify(y));