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Can destructuring an array be used to map properties of each elements?

Suppose there is an array like this:
const a = [ {p:1}, {p:2}, {p:3} ];
Is it possible to destructure this array in order to obtain p = [1, 2, 3] ?
Because this does not work :
const [ ...{ p } ] = a; // no error, same as const p = a.p;
// p = undefined;
Edit
In response to all the answers saying that I need to use Array.prototype.map, I am aware of this. I was simply wondering if there was a way to map during the destructuring process, and the answer is : no, I need to destructure the array itself, then use map as a separate step.
For example:
const data = {
id: 123,
name: 'John',
attributes: [{ id:300, label:'attrA' }, { id:301, label:'attrB' }]
};
function format(data) {
const { id, name, attributes } = data;
const attr = attributes.map(({ label }) => label);
return { id, name, attr };
}
console.log( format(data) };
// { id:123, name:'John', attr:['attrA', 'attrB'] }
I was simply wondering if there was a way, directly during destructuring, without using map (and, respectfully, without the bloated lodash library), to retrive all label properties into an array of strings.

Honestly I think that what you are looking for doesn't exist, normally you would map the array to create a new array using values from properties. In this specific case it would be like this
const p = a.map(element => element.p)
Of course, there are some packages that have many utilities to help, like Lodash's map function with the 'property' iteratee

you can destructure the first item like this :
const [{ p }] = a;
but for getting all values you need to use .map
and the simplest way might be this :
const val = a.map(({p}) => p)

Here's a generalized solution that groups all properties into arrays, letting you destructure any property:
const group = (array) => array.reduce((acc,obj) => {
for(let [key,val] of Object.entries(obj)){
acc[key] ||= [];
acc[key].push(val)
}
return acc
}, {})
const ar = [ {p:1}, {p:2}, {p:3} ];
const {p} = group(ar)
console.log(p)
const ar2 = [{a:2,b:1},{a:5,b:4}, {c:1}]
const {a,b,c} = group(ar2)
console.log(a,b,c)

How can I store previous values instead of storing the value in array of objects in react state

I am storing the prev values in an array of objects, for example [{ActFollow: 'BlN'},{ActSendGift: 'BlY'},{ActSubscribe: 'BlY'}] I want to store the key and values in an object like this {ActFollow: 'BlN',ActSendGift: 'BlY', ActSubscribe: 'BlY'}
const [activityTypes, setActivityTypes] = useState<any>([]); // state
.then((response: any) => {
setActivityTypes((oldArray: any) => [
...oldArray,
{[item.channelSettingTypeId]: response.settingValue},
]);
});

How about this, if the nesting is only one level deep
const data = [{ActFollow: 'BlN',ActSendGift: 'BlY', ActSubscribe: 'BlY'}]
console.log([{...data[0],"hey" : "world"}])

const items = [{ActFollow: 'BlN'},{ActSendGift: 'BlY'},{ActSubscribe: 'BlY'}]
let object = {}
items.forEach(item=>{
for (const [key, value] of Object.entries(item)) {
object = {
...object,
[key]: value
}
}
})
console.log(object)
You can use this simple idea in React also. Just hold on the default empty object in state and update the object.

You can reduce the array of objects into an object.
You can do it by spreading (...) the current object into the resultant object, as shown below:
const
arrOfObjs = [{ ActFollow: "BlN" }, { ActSendGift: "BlY" }, { ActSubscribe: "BlY" }],
obj = arrOfObjs.reduce((res, o) => ({ ...res, ...o }), {});
console.log(obj);
You can also do it using Object.assign, as shown below:
const
arrOfObjs = [{ ActFollow: "BlN" }, { ActSendGift: "BlY" }, { ActSubscribe: "BlY" }],
obj = arrOfObjs.reduce((res, o) => Object.assign(res, o), {});
console.log(obj);

Use Spread Operator
const items = [{ActFollow: 'BlN', Anurag: 26},{ActSendGift: 'BlY'},{ActSubscribe: 'BlY'}]
let obj ={}
items.forEach((item) => {
obj = {
...obj,
...item
}
})
console.log(obj)

Javascript - Access a nested property on an object from an array of strings

I have an object like this
{
metadata: {
correlationId: 'b24e9f21-6977-4553-abc7-416f8ed2da2d',
createdDateTime: '2021-06-15T16:46:24.247Z'
}
}
and I have an array of the properties I wanna access
[metadata, correlationId]
how can I dynamically access the property on the object?
like
keys.forEach((key) => {
object[key][key2] ???
})
it needs to be dynamic since I don't know how deep we need to access the object

Here is a solution without recursion:
const myObj = {
a: {
b: {
c: "I'm the target"
}
}
}
const keys = ['a', 'b', 'c'];
let result = myObj;
for (const key of keys) {
result = result[key];
}
console.log(result);
Or with recursion:
const finder = (obj, keys, index = 0) => {
const result = obj[keys[index++]];
if (!result) {
return obj;
}
return finder(result, keys, index);
}
console.log(finder(myObj, keys));

This is pretty similar to Accessing nested JavaScript objects and arrays by string path, except with one fewer step - you already have the keys you need in the form of an array. .reduce and access the next nested value in each iteration.
const obj = {
metadata: {
correlationId: 'b24e9f21-6977-4553-abc7-416f8ed2da2d',
createdDateTime: '2021-06-15T16:46:24.247Z'
}
};
const keys = ['metadata', 'correlationId'];
const result = keys.reduce((a, key) => a[key], obj);
console.log(result);

This is my idea to solve your problem. Tell me, if is ok for you.
let x = {
metadata: {
correlationId: 'b24e9f21-6977-4553-abc7-416f8ed2da2d',
createdDateTime: '2021-06-15T16:46:24.247Z'
}
}
let fun = x => typeof x === 'string' ? console.log(x) : Object.keys(x).map( y => fun(x[y]));
fun(x);

convert set to object

I have a set which needs to be converted into an object with the set's unique values as the object keys and an empty string as each element's value in the object.
Here is the set I'm working with:
const uom = new Set(['inches', 'centimeters', 'yards', 'meters']);
I've tried this:
const uomObj = {...[...uom]};
console.log(uomObj);
Which yields this:
Object {
"0": "inches",
"1": "centimeters",
"2": "yards",
"3": "meters",
}
but that does not match the desired result of:
Object {
"inches": "",
"centimeters": "",
"yards": "",
"meters": "",
}
Can this be achieved with an ES6 approach? If so, how?

You can use Array.from with a mapping function to convert each value inside your set into an object and then use Object.assign() with the spread syntax to merge the array of objects into a single resulting object like so:
const uom = new Set(['inches', 'centimeters', 'yards', 'meters']);
const res = Object.assign(...Array.from(uom, v => ({[v]:''})));
console.log(res);

Create an object, then loop over the values in the set and create a property for each one. The reduce method is probably the most compact way to do that.
const uom = new Set(['inches', 'centimeters', 'yards', 'meters']);
const result = Array.from(uom).reduce( (a,c) => { a[c]=""; return a; }, {});
console.log(result);

Here's one way:
[...uom].reduce((o, u) => {
o[u] = '';
return o;
}, {})

You can use Array.prototype.reduce to get the elements from the set and accumulate it in an object:
const uom = new Set(['inches', 'centimeters', 'yards', 'meters']);
const getObjectFromSet = (set) => {
return [...set].reduce((r, k) => {r[k] = ""; return r; },{});
}
console.log(getObjectFromSet(uom));
You can also use the Object.fromEntries for ES6+ code:
const uom = new Set(['inches', 'centimeters', 'yards', 'meters']);
const getObjectFromSet = (set) => {
return Object.fromEntries(Array.from(set, (k) => [k, ""]));
}
console.log(getObjectFromSet(uom));

For anyone like myself who was looking for the reverse of this for something similar to the below
Object {
"length": "inches",
"length": "centimeters",
"length": "yards",
"length": "meters",
}
This code worked for me
const mySet = new Set(['inches', 'centimeters', 'yards', 'meters']);
let newArr = [];
const setToObj = [...mySet].map(el => {
newArr.push({ 'length': el });
});

convert objects array to griddle readable array

I'm fetching json data with ajax. Then I want to output it in Griddle using griddle-react. The problem is I cannot convert my array to a Griddle readable array.
After the ajax fetch i made a callback function:
function convert(obj) {
console.log(obj);
Object.keys(obj).forEach(function (key) {
let format = JSON.stringify(obj[key]);
console.log(format);
self.setState(() => ({ data: key[format] }));
});
}
The first console.log output looks like this:
{
{
"BTC": {
"opening_price": "9845000",
"closing_price": "9967000",
"min_price": "9814000",
"max_price": "10047000",
"average_price": "9928071.5654",
"units_traded": "7242.04659594",
"volume_1day": "7242.04659594",
"volume_7day": "73491.92898643",
"buy_price": "9967000",
"sell_price": "9968000"
},
}
}
My functions makes it look like this: (second console.log):
{
"opening_price": "9846000",
"closing_price": "9965000",
"min_price": "9814000",
"max_price": "10047000",
"average_price": "9929422.0905",
"units_traded": "7200.46713802",
"volume_1day": "7200.467F13802",
"volume_7day": "73395.33311647",
"buy_price": "9959000",
"sell_price": "9964000"
}
I want it to convert to the following array, basically adding the name item, and thereafter Griddle can read it:
{
"name": "BTC",
"opening_price": "9845000",
"closing_price": "9967000",
"min_price": "9814000",
"max_price": "10047000",
"average_price": "9928071.5654",
"units_traded": "7242.04659594",
"volume_1day": "7242.04659594",
"volume_7day": "73491.92898643",
"buy_price": "9967000",
"sell_price": "9968000"
},
What I'm doing wrong here? I'm sure its pretty close to what I want, but I can't figure it out at this point.

You can use Object.entries to get the keys and values. Use Object.assign to make new objects
var obj = {
"BTC": {"opening_price": "9845000","closing_price": "9967000","min_price": "9814000","max_price": "10047000","average_price": "9928071.5654","units_traded": "7242.04659594","volume_1day": "7242.04659594","volume_7day": "73491.92898643","buy_price": "9967000","sell_price": "9968000"}
}
var newObj = Object.entries(obj).reduce((c, [i, v]) => Object.assign(c, {name: i}, v), {});
console.log(newObj);
If you have several keys, you can use map
var obj = {
"BTC": {"opening_price": "9845000","closing_price": "9967000","min_price": "9814000","max_price": "10047000","average_price": "9928071.5654","units_traded": "7242.04659594","volume_1day": "7242.04659594","volume_7day": "73491.92898643","buy_price": "9967000","sell_price": "9968000"},
"OTH": {"opening_price": "9845000","closing_price": "9967000","min_price": "9814000","max_price": "10047000","average_price": "9928071.5654","units_traded": "7242.04659594","volume_1day": "7242.04659594","volume_7day": "73491.92898643","buy_price": "9967000","sell_price": "9968000"},
}
var newArr = Object.entries(obj).map(([i, v]) => Object.assign({}, {name: i}, v));
console.log(newArr);
Without including date property
var obj = {
"KNC": {"opening_price": "2731","closing_price": "2788","min_price": "2693","max_price": "2849","average_price": "2790.5368","units_traded": "3178032.25814499211673","volume_1day": "3178032.25814499211673","volume_7day": "110687333.315264505902311000","buy_price": "2783","sell_price": "2788"},
"date": "1525269153470"
}
var newObj = Object.entries(obj).reduce((c, [i, v]) => i !== 'date' ? Object.assign(c, {name: i}, v) : c, {});
console.log(newObj);

Can you update your function to have this line in it?
obj[key]["name"] = key
function convert(obj) {
console.log(obj);
Object.keys(obj).forEach(function (key) {
obj[key]["name"] = key;
let format = JSON.stringify(obj[key]);
console.log(format);
//self.setState(() => ({ bithumbData: key[format] }));
});
}

function convert(obj){
var parentKey = Object.keys(obj)[0];//Getting parent first element key
obj = obj[parentKey];
var newObj = {}; //Creating new empty jason object
newObj['name'] = parentKey; //key apply as name element to new jason object
for(var key in obj) //looping each child element
newObj[key] = obj[key]; //child applying to new jason object
return newObj;
}
console.log(JSON.stringify(convert(obj)));