Questions tagged as 'ecmascript-2015'

Tagged questions
2
answers

What is a Symbol for in JavaScript? (ES6)

Reading the MDN documentation where we talk about the primitive data Symbol for more that I read and reread I do not understand what would be a use case for that element more than to iterate Symbol.iterator . The documentation sa...
asked by 29.12.2015 / 18:58
2
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Points and commas in JS, Recommended at performance level?

I know that the use of; in JS, but for the JS interpreter that is more efficient, what do we say or not?     
asked by 15.03.2018 / 14:35
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var, let, const ... or nothing in Javascript

The following question: When it is convenient to use var, let and const in ECMA Script 6? responds in part to my question, but not entirely. Reading the accepted answer, I understood that: let declares a local scope variable...
asked by 29.09.2017 / 16:56
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What is the meaning of "... args" in the argument of a Javascript function?

Reading a bit of Javascript code, I've come across this: router.route('/:id') .put((...args) => controller.update(...args)) .get((...args) => controller.findById(...args)); Is anyone clear about what ... args means?     
asked by 12.02.2017 / 20:07
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What is the meaning of static get in Javascript?

An expression in Javascript has left me a bit confused: static get is() { return "custom-element"; } What is the operation of a static get in Javascript? I guess the static has a function similar to what is done in Java or C ++.     
asked by 19.03.2017 / 17:30
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answer

How to set up Visual Studio 2015 Community Update 3 to work with ES6 (jsx files)

Good day, I'm starting in the library react JS, I would like to know how is the correct way to configure visual studio 2015 community to work with react using ES6 and also be able to create jsx files, right now creating a file with that extensio...
asked by 20.10.2016 / 18:21
1
answer

Understanding async / await

Environment: sequelize 3.27, node.js 6.1, express sequelize Object.hasMany(OtherObject) I have the following piece of code: //... await db.Object.create(objectData).then(async (object:any) => { //.. object.update({sharedL...
asked by 12.06.2017 / 15:08
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Export and import modules with ES6 error?

I am trying to learn how to export and import modules in ES6 and it tells me in the console: SyntaxError: export declarations may only appear at top level of a module I'm trying something simple. I have the code so that: archivo.js e...
asked by 20.03.2017 / 01:00
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Use of fetch javascritp. And receive data with express

I have a question. You will see I am sending the data of my form with help of fetch like this: const formSignin = document.querySelector('#formSignin'); formSignin.addEventListener("submit", event => { event.preventDefault(); con...
asked by 23.01.2018 / 21:28
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How to order a web page to show it

My application uses token-based authentication. On the login page, I send the user's data and password. I must receive a token to set it to localStorage . once it is received and established. render the welcome page. This is my Front end c...
asked by 25.01.2018 / 15:56