Questions tagged [es6-class]
This tag is for questions regarding Classes in Ecmascript 6. The tag is only for classes provided in the Ecmascript version.
es6-class
1,272
questions
0
votes
1
answer
34
views
Why is inheritance using constructor functions "hard to do properly" (MDN)?
The MDN's article for "Inheritance and the prototype chain", under "Different ways of creating and mutating prototype chains": "With constructor functions", gives the ...
- 304
1
vote
1
answer
67
views
JavaScript class with static methods vs object with function properties
In JavaScript (and TypeScript) is there any difference between using a class vs an object to namespace methods from a performance perspective? And are there any other reasons to prefer one option over ...
- 116
0
votes
1
answer
32
views
Get value of private variable in extension method ES6 class in JavaScript
I have a JavaScript ES6 class in a library that uses some private base values to compute another value.
Abstracted and simplified the situation is something like this:
class Example {
#apples;
#...
- 155
0
votes
1
answer
65
views
Detect direct instances in JavaScript
A couple of years ago, I wanted figure how to create a type check for class A that returns true only for objects instantiated by new A(). For this, I wrote the class like this:
class A {
static #...
- 2,704
-2
votes
3
answers
85
views
How to correctly implement a 'Child' class that extends a 'Parent' class and inherits a class field from the latter?
This is my task
Implement a Child class that extends the Parent.
Add a constructor to the Child class can calls super().
Implement a new function addNewAbilities(newAbility) in the Child class where ...
1
vote
2
answers
87
views
Change prototype chain in multiple level class inheritance
Since JS doesn't allow to extends more than one class, we could be with a complex inheritance chain like this
class Level1 {
constructor() {
this.level = 1;
}
method1() {
...
- 133
0
votes
1
answer
80
views
Extending a JavaScript ES6+ class that explicitly returns an object in its constructor
I'm having issue with extending a Javascript ES6+ class that returns an object from the constructor.
Take for example:
class Base {
constructor() {
return {name: "base"}
}
}
class ...
- 58
0
votes
0
answers
54
views
Sequelize Models, registered, synced, but how to do CRUD-Operations?
i used a course on udemy to make my first steps with sequelize: https://github.com/DavidArmendariz/sequelize-course/tree/master
Because I only want to use ES-Modules I had to make a few adjustments.
...
0
votes
1
answer
81
views
ES6 classes extends a class with returning constructor
In the following code I have an unexpected behaviour for me. I was waited to see the method A2::method() to be called, but it is A0::method() instead.
More tests showed me that if A1 returns something,...
- 1,484
0
votes
2
answers
78
views
verbose class definition in TypeScript
I have a class with a destructured constructor parameter:
import * as ē from 'three'
export class cylindricCurve extends ē.Curve {
#scale: number
#eqs: ((θ: number) => number)[]
#rounds: ...
- 4,371
1
vote
2
answers
301
views
How to extend Array to enforce specific arguments in TypeScript?
I'm using TypeScript and I want to extend Array to enforce a specific argument. This way, I can make sure that whenever I create a FruitArray, the first element is a fruit.
So I tried extending Array ...
- 5,700
0
votes
2
answers
55
views
Why I can't use 'super' in prototype method definition when I can use Object.getPrototypeOf(this.constructor.prototype)?
So I tested this code:
class C1 {}
C1.prototype. f =function(){ return 1 }
class C2 extends C1 {}
C2.prototype. f =function(){ return super.f()+1 }
And it throws a syntax error: 'super' keyword ...
- 93
0
votes
2
answers
133
views
Is it possible to modify properties of multiple objects or class instances all at once with one line of code?
In JavaScript (assuming version is >= ES6), say that I have a class;
class MyClass {
constructor() {
this.property = null;
}
}
... and I create two new instances of the class;
let inst1 = ...
user22588911
0
votes
0
answers
36
views
Create class constructor using eval: getting ReferenceError
I'm trying to create class constructor dynamically and came acrosss the following solution:
https://stackoverflow.com/a/40069309/1713920
//TeamMemberProfile.js
export default class TeamMemberProfile{
}...
- 10.5k
0
votes
0
answers
61
views
Dynamically serialise and restore ES6 class types in javascript
Is it possible to serialize ES6 class type having object instance? How?
class MyClass {
}
let myClass = new MyClass()
//store class type
let clazzTypeString = serializeClassTypeToString(myClass)
let ...
- 10.5k