Function groupBy

Alias

groupBy<T, K>(arr, getKeyFromItem): Record<K, T[]>
Groups the elements of an array based on a provided key-generating function.

This function takes an array and a function that generates a key from each element. It returns an object where the keys are the generated keys and the values are arrays of elements that share the same key.
Type Parameters
- T
  The type of elements in the array.
- K extends PropertyKey
  The type of keys.
Parameters
- arr: readonly T[]
  The array to group.
- getKeyFromItem: ((item: T) => K)
  A function that generates a key from an element.
  - - (item): K
    - Parameters
      item: T
      Returns K
Returns Record<K, T[]>
An object where each key is associated with an array of elements that share that key.
Example
```
const array = [
  { category: 'fruit', name: 'apple' },
  { category: 'fruit', name: 'banana' },
  { category: 'vegetable', name: 'carrot' }
];
const result = groupBy(array, item => item.category);
// result will be:
// {
//   fruit: [
//     { category: 'fruit', name: 'apple' },
//     { category: 'fruit', name: 'banana' }
//   ],
//   vegetable: [
//     { category: 'vegetable', name: 'carrot' }
//   ]
// }
```
- Defined in src/array.ts:17