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Questions tagged [object-destructuring]

Use this tag for JavaScripts object destructuring syntax.

JavaScript object destructuring allows one to replace code like:

const object = {foo: 'bar', baz: 'bing'};
const foo = object.foo;
const baz = object.baz;

With this destructuring assignment syntax:

const object = {foo: 'bar', baz: 'bing'};
const {foo, baz} = object;
155 questions
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Escape reserved keywords in object destructing assignment

Is it possible to use reserved keywords in an object destructing assignment. Specifically I am trying to handle JSON with property property named default. //Doesn't compile class FooBar { constructor({foo, default}) { this.foo = foo; …
Steven Wexler
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how to bind data to this by destructuring assignment?

I wanna add new key and value to this object by destructuring assignment, but it falls in error: Uncaught SyntaxError: Unexpected token : Let see my example, assume I have obj data object: const obj = { 'a':'1', 'b':'2', …
AmerllicA
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object destructing inside constructor in nodejs to assign values to member variable not working

I am trying ES6 object destructuring inside a constructor hoping to assign value to a member variable. It is not working. Its showing undefined when I am printing the value inside a member function. Its printing correctly if I print inside the…
KKB
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Why destructuring assignment doesn't know null value as falsy and use default value?

Assume we have a function that use some keys in the inner object of argument: const api = ({ data: { name } = {} }) => `My name is ${name}.`; If we pass {}, { data: '' }, { data: 0 }, { data: NaN } or { data: undefined } to the function we will…
AmerllicA
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What's the best way to use a type assertion with destructuring assignment?

I have some code using destructuring assignment as follows: const { values: project, setValues, submitForm } = useFormikContext(); Per the TypeScript type assertion documentation I'd like to use the as keyword to tell the TS compiler that project…
mikemaccana
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Can you destruct an object and have nullish coalescing for potential undefined constants?

I use React, so I have a props object, for example: const props: { id: number, name?: string} = { id: 1 }; // not defining the `name` const { id, name } = props; // here the `const name` becomes undefined forever and even if I use the defaultProps…
Nikolai
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Enforcing TSX prop type inline for function declaration which declares props using object destructuring

I have a custom Type export class MyClass { name: string; img: string; constructor(name: string) { this.name = name; this.img = `/images/${name}.jpg`; } } I have a stateless functional component which takes that type as a…
Sam
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How to destructure an object based on a dynamic defined variable

I am working with an immutable object that I need to add subtract an array of values from. I know it's possible using ES6 destructing with the following. const {countries, remainder} = someObj // {countries:...,languages:..., ...keys}; This will…
Vincent Rye
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Why there is a problem with destructuring ES6 on declared object?

I have a problem, or more some weird situation. I am using https://es6console.com. I want to use destructuring and assign properties to already declared variables. It looks like that there is a problem in where I declare object. Please open…
zamf123
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destruct object with interface

I have this code: const {items} = this.props; but, I need to set the interface into the items constant and I do not want to do this: const items: ItemsInterface = this.props.items Possible?
Ivan Hanák
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TypeScript imports vs. ES6 object destructuring

With TS imports, I believe I can do this: import {foo as bar} from 'foo'; with ES6 object destructuring in JS or TypeScript - is there a way to rename an "imported value" in the same way? For example, const {longVarName as lvn} = x.bar;
Alexander Mills
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Need help understanding what is happening in object destructuring for React component

I was watching a video about layout components and I saw that the author seemed to destructure the parameters but also assign it as a property in an object (as seen in Splitscreen.js)? I was wondering if anyone could help me understand what is going…
CMS
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Object destructuring in typescript

Is it possible to destructure an object which comes from an function call without Typescript complaining? File 1 React Component 1 ... let obj = null // <-- object initialization ... useEffect(() => { obj = functionCall(...) // <-- function call…
eakl
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How to destructure an array of objects into multiple arrays of its keys?

My data set is an array of objects which all have only two keys (id and name): [{ id: 1, name: 'Foo'}, { id: 2, name: 'Bar'}, { id: 3, name: 'FooBar'}, { id: 4, name: 'BarFoo'}] I want to destructure them in such a way that I end up having an…
leonheess
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Object destructuring assignment with default value of itself

I need to destruct an object that some of the variables may already have a value. let foo = 1, bar, baz = 'Hello'; const config = { foo: 42 }; ({ foo, bar, baz } = config); console.log({ foo, bar, baz }); This gives me { "foo": 42, "bar":…
Hao Wu
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