Javascript - ERROR : TS2339: Property 'group' does not exist on type '{ rootCause: string; countermeasure?: any; signalName: any; importance: any; }[]'

LakshayRohilla
June 28, 2023
175 views
0 votes
2 Answers

Code:

var dataArray: { rootCause: string, countermeasure?: any, signalName: any, importance: any }[] = []
dataArray.push({
            rootCause: x.description,
            countermeasure: response.countermeasures[ii],
            signalName: x.signalName,
            importance: x.importance
          })
const result = dataArray.group((data: any) => data.rootCause);

I`m just having an array of objects, and group method is for array itself.

Error:

TS2339: Property 'group' does not exist on type '{ rootCause: string; countermeasure?: any; signalName: any; importance: any; }[]'.

In the above code, group method is underlined with the red color.

Official docs to check its working click me

In there, its mentioned that its an experimental one, not sure if we could use it or not.

Similar question click me to what I asked, but mine is not solved.

I made an example code to try out group() on https://onecompiler.com/javascript/, though in the compiler it says "group is not function" :

By this should I conclude that we cant use group method for array?

Answers

Chosen as BEST ANSWER
- LakshayRohilla
- June 28, 2023 at 11:50 am
- 0 votes
0
Alright, So official group() method is not working as intended. Check it out here

But we could have our own walkaround for it.

Let say the data that we have is as follows:
```
const products = [
  { name: 'apples', category: 'fruits' },
  { name: 'oranges', category: 'fruits' },
  { name: 'potatoes', category: 'vegetables' }
];
```
Required output:
```
const groupByCategory = {
  'fruits': [
    { name: 'apples', category: 'fruits' }, 
    { name: 'oranges', category: 'fruits' },
  ],
  'vegetables': [
    { name: 'potatoes', category: 'vegetables' }
  ]
};
```
Code:
```
const groupByCategory = products.reduce((group, product) => {
  const { category } = product;
  group[category] = group[category] ?? [];
  group[category].push(product);
  return group;
}, {});

console.log(groupByCategory);
```
ScreenShot of the output : For more detailed information check here .