ecmascript-6 Archives - Page 7 of 9

What are the actual uses of ES6 WeakMap?

What are the actual uses of the WeakMap data structure introduced in ECMAScript 6? Since a key of a weak map creates a ...

May 4, 2022
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Map vs Object in JavaScript

I just discovered this feature: Map: Map objects are simple key/value maps. That confused me. Regular JavaScript objects are dictionaries, so how is ...

May 4, 2022
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What’s the meaning of “=>” (an arrow formed from equals & greater than) in JavaScript?

I know that the >= operator means more than or equal to, but I’ve seen => in some source code. What’s the meaning ...

May 3, 2022
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Node.js – SyntaxError: Unexpected token import

I don’t understand what is wrong. Node v5.6.0 NPM v3.10.6 The code: function (exports, require, module, __filename, __dirname) { import express from 'express' ...

May 3, 2022
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How can I clone a JavaScript object except for one key?

I have a flat JS object: {a: 1, b: 2, c: 3, ..., z:26} I want to clone the object except for one ...

May 3, 2022
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Private properties in JavaScript ES6 classes

Is it possible to create private properties in ES6 classes? Here’s an example. How can I prevent access to instance.property? class Something { ...

May 2, 2022
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Object spread vs. Object.assign

Let’s say I have an options variable and I want to set some default value. What’s is the benefit / drawback of these ...

May 2, 2022
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ES6 class variable alternatives

Currently in ES5 many of us are using the following pattern in frameworks to create classes and class variables, which is comfy: // ...

May 2, 2022
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How to update nested state properties in React

I’m trying to organize my state by using nested property like this: this.state = { someProperty: { flag:true } } But updating state ...

May 1, 2022
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How to add multiple classes to a ReactJS Component?

I am new to ReactJS and JSX and I am having a little problem with the code below. I am trying to add ...

May 1, 2022
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