What does this constant definition mean [duplicate] - javascript

This question already has answers here:
What is destructuring assignment and its uses?
(3 answers)
Closed 8 months ago.
What does this assignment mean?
const { data: scoreData } = useMostRecentScore(studentId, loginId)


If useMostRecentScore returns an object, with a data property, it will create a new variable called scoreData and assign the contents of the data property.

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how to destruct this object with customer:id [duplicate]

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I have an object with this data structure returned by api:
const obj = {customer:id: '123'}
How should I destruct this object? Thanks

JavaScript object like String literal doesn't to set property [duplicate]

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In JavaScript everything is object like String literal, numbers, Object...
And properties can be added to objects dynamically also, but I am adding property to object which refer to string then it seems it is not working
Following is JS code which I am running
var aVar = "some string";
console.log(aVar);
aVar.name = 'raj';
console.log(aVar.name);
Output...
hi
some string
undefined

Is it possible to create a ES6 Javascript expression whose value is an object with a dynamic property name? [duplicate]

This question already has answers here:
How to use a variable for a key in a JavaScript object literal?
(16 answers)
Closed 4 years ago.
I currently do:
function outer(prop_name) {
const tmp = {};
tmp[prop_name] = 'hello world';
foo(tmp);
}
Is there a way of rewriting this as:
foo(<expression>)
using an expression involving prop_name?

You can write it as
foo({ [prop_name] : 'hello_world'});

What is the main difference between array and object in js [duplicate]

This question already has answers here:
What’s the difference between “{}” and “[]” while declaring a JavaScript array?
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Closed 4 years ago.
The point of confusion is - when we check the type of array or object using typeof get the return value as Object. So what's the main difference between them.

You can check using constructor.name
const myArr = []
const myObj = {}
console.log(`myArr is an ${myArr.constructor.name}`)
console.log(`my Obj is an ${myObj.constructor.name}`)

In Javascript, can I reference a key value pair from another key value pair? [duplicate]

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Self-references in object literals / initializers
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var fighters = ['johnjones', 'rondarousey', 'connormcgregor', 'chuckliddel', 'demetriusjohnson'];
var warriors = {
wrestlers: ['randysavage', 'hulkhogan', 'ultimatewarrior', 'jakethesnake', 'milliondollarman'],
stable: [fighters, warriors.wrestlers]
}
I believe I can reference fighters from stable, but can I reference wrestlers from stable? In other words, how do I reference a key value pair from a later key value pair within the warriors object. Thank you for any and all help!

You cannot do that until the variable warriors is initialized. The only way is to wait and assign in the next line:
var warriors = {
wrestlers: ['randysavage', 'hulkhogan', 'ultimatewarrior', 'jakethesnake', 'milliondollarman'],
}
warriors.stable = [fighters, warriors.wrestlers]
Or use some kind of weird initialization like the one described here. Or use function constructor.

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