The latest version of JavaScript, ECMAScript 2024, became an official standard on June 26, 2024, thanks to the 127th ECMA General Assembly.
It has included six new features
- Grouping synchronous iterable
- Promise.withResolvers()
- Regular expression flag /v
- New features for ArrayBuffers and SharedArrayBuffers
- Ensuring that strings are well-formed
- Atomics.waitAsync()
Grouping synchronously iterable
groupBy() : Object.groupBy() Map.groupBy()
The Object.groupBy() method takes an object and a callback function. It groups the object's elements into a new object based on the strings returned by the callback function for each element. The original object remains unchanged.
const stationary=[
{name:'Pencil',qty:100},
{name:'Pen',qty:50},
{name:'Rubber',qty:300},
{name:'Notebook',qty:150},
{name:'Scale',qty:0},
{name:'Color Pencil',qty:0},
]
function callbackFun({qty}){
return qty>0?'available':'notAvailable'
}
const result=Object.groupBy(stationary,callbackFun);
console.log(result);
//output
/*
{
available: [
{ name: 'Pencil', qty: 100 },
{ name: 'Pen', qty: 50 },
{ name: 'Rubber', qty: 300 },
{ name: 'Notebook', qty: 150 }
],
notAvailable: [
{ name: 'Scale', qty: 0 },
{ name: 'Color Pencil', qty: 0 }
]
}
*/
The Map.groupBy() method groups elements from an object based on strings returned by a callback function. It creates a new Map object with these groups, leaving the original object unchanged.
//...
const result=Map.groupBy(stationary,callbackFun);
console.log(result);
//output
/*
Map(2) {
'available' => [
{ name: 'Pencil', qty: 100 },
{ name: 'Pen', qty: 50 },
{ name: 'Rubber', qty: 300 },
{ name: 'Notebook', qty: 150 }
],
'notAvailable' => [
{ name: 'Scale', qty: 0 },
{ name: 'Color Pencil', qty: 0 }
]
}
*/
Checkout next Post for other features
Reference Ecma International approves ECMAScript 2024: What’s new?
Happy Coding !!
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