This question already has answers here:
How to fix Eslint error "prefer-destructuring"?
(3 answers)
Closed 11 months ago.
I am codding first time on Vue.js and I have problem. Can you describe me the solution or problem.enter image description here
const { data } = await ...
Use this in 108 and 97 lines.
Your promise object has a data element. Currently, you are accessing your data element using dot (.) syntax. ( Your promise object.data is returning data).
You can use object destructuring to directly access the data element from inside your promise object
const { data } = (await this.$api.auth.sighIN({
email: this.email,
password: this.form.password,
}));
Related
This question already has answers here:
Spread Syntax vs Rest Parameter in ES2015 / ES6
(11 answers)
What is the meaning of "foo(...arg)" (three dots in a function call)?
(4 answers)
Closed 1 year ago.
I have this working code (puppeteer) :

async function extractedEvaluateCall(page) {
await page.waitForXPath(xpath);
const links = await page.$x(xpath);
const results = await page.evaluate((...links) => {
return links.map(e => e.innerText);
}, ...links);
}
What does the notation ... does here ?
I tried without, it doesn't work:
UnhandledPromiseRejectionWarning: TypeError: Converting circular structure to JSON Are you passing a nested JSHandle?
links is already an array, why the need of spread operator ?
This question already has answers here:
access object through dot-syntax string path
(2 answers)
Convert a JavaScript string in dot notation into an object reference
(34 answers)
Accessing nested JavaScript objects and arrays by string path
(44 answers)
Closed 2 years ago.
I am having a problem which I think I might have figured out before how to do it but I can't remember now and can't figure it out.
Let's say we have an object thats a few levels deep, meaning it has as values other objects which also have as some of the values objects and so on.
Now how could I make a function to which I pass the object and and adress inside it and I can access the value at that location inside the function like this:
const getValueAtAdress = (object, 'country.city.rules') => {
return //here I need to return the value at object.country.city.rules.
}
Am I missing something obvious?
I thought I'd mention here for posterity that what helped me was the answer using the reduce which is exactly what I used before but I could not remember:
Example that I am using for my particular problem:
let stateLocation = address.split('.').reduce((acc, cur) => acc[cur], state);
Your code shows a function declaration but you can't declare an argument name in quotes
You can however call a function and pass a string.
In that case, you just need to split the string into an array and then loop over that array, building up a "chained" set of string indexes that can be passed to the object. The String.split() and Array.reduce() methods are the key.
let obj = {
county: {
city: {
rules: "Strict"
}
}
};
const getValueAtAddress = (object, countyCityRules) => {
// Split the string at the dots to form an array...
// The loop over that array and reduce it with an
// accumulator that is then applied to the object.
return countyCityRules.split(".").reduce((acc, cur) => acc[cur], obj);;
}
console.log(getValueAtAddress(obj, "county"));
console.log(getValueAtAddress(obj, "county.city"));
console.log(getValueAtAddress(obj, "county.city.rules"));
This question already has answers here:
ECMAScript 6 arrow function that returns an object
(6 answers)
Closed 3 years ago.
I have an array of strings that I get from an endpoint and I need to convert it to key-value pairs for the frontend to display them correctly. I have tried different concepts such as reduce and map but have not been able to get it working successfully. I assume it might be one-liner for someone familiar with FE but has taken forever for a BE person like me.
Here is what I have tried:
var input = ['quiz1', 'quiz2'];
const mapping = input.map(x => {"id":x, "label":x};);
console.log(mapping);
I am expecting an output of the format
[{"id":"quiz1", "label":"quiz1"}, {"id":"quiz2", "label":"quiz2"}]
Thanks for looking!
It's simply two syntax errors:
var input = ['quiz1', 'quiz2'];
const mapping = input.map(x => ({"id":x, "label":x}));
console.log(mapping);
Firstly, no semicolon in a un-braced arrow function body.
This is invalid: (() => 3;). This is valid: (() => 3).
Secondly, wrap return obj in ().
This is invalid: () => {x: 3}. This is valid: () => ({x: 3}).
This question already has answers here:
What is the difference between const and const {} in JavaScript
(4 answers)
Closed 4 years ago.
So while I was making my react native app, I tried to use an API from
https://github.com/uport-project/react-native-uport-connect and there is a syntax that I've yet to understand.
May I know what does const { uport, MNID } mean from this code
import configureUportConnect from 'react-native-uport-connect'
const { uport, MNID } = configureUportConnect({
appName: 'uPort Demo',
appAddress: '2oeXufHGDpU51bfKBsZDdu7Je9weJ3r7sVG',
privateKey:'<PRIVATE_KEY>',
})
Im quite new to this and this code is placed on a seperate js file and im trying to export const { uport, MNID } so I could use it in my Components and im not sure if it's a variable, object or some js syntax. Thank you!
This is called destructuring, and it means you are assigning your variables, not to the object that the function returns, but to the individual properties of that object, specifically the properties at the keys uport and MNID. The alternative syntax would be to say const variableName = // etc... and then you would access the properties like: variableName.uport.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment#Object_destructuring
This question already has answers here:
Accessing nested JavaScript objects and arrays by string path
(44 answers)
Access Javascript nested objects safely
(14 answers)
Test for existence of nested JavaScript object key
(64 answers)
Closed 5 years ago.
I'm using v4 sheets API from google-api-nodejs-client, it returns a lot of data. Though I filter it using fields arguments, the structure of JSON is very complex. So to incorporate it into my logic, I flatten it. And it needs to be safe, I don't want any exceptions to be thrown.
This is how the UNSAFE version of the code looks:
const data = response.sheets[0].data;
const columns = data.map((column) => {
const rowData = column.rowData;
const values = rowData[0].values;
return rowData.map((cellData) => cellData.values[0].userEnteredValue);
});
// ...
If JSON is invalid, an exception is inevitable. I don't want this. The problem is that to fix it, I should add plenty of if-s. This would make the code look ugly.
Let's summarize: Is there a way to map JSON into local objects safely and expressive (and preferably relying only on features of ES6)?
UPDATE
Let's add a little more context. This is a small insight how deep the JSON is, and all I need to map it to an array of strings ('1.06' is one of them).
{
"sheets":[
{
"data":[
{
"rowData":[
{
"values":[
{
"userEnteredValue":{
"stringValue":"1.06"
}
}
]
},
...