Function groupBy

groupBy<T = never, K = never>(
    array: K[],
    setterPropertyName: (
        element: K,
        index?: number,
    ) => string | number | symbol,
    transform?: (element: K) => T,
): PRecord<([T] extends [never] ? K : T)[]>
Groups elements of an array based on a key provided by a callback function.
Type Parameters
- T = never
  The type of elements in the array.
- K = never
Parameters
- array: K[]
  The target array.
- setterPropertyName: (element: K, index?: number) => string | number | symbol
  A callback function that gets the key of each group.
- Optionaltransform: (element: K) => T
  A function that transforms each element before grouping.
Returns PRecord<([T] extends [never] ? K : T)[]>
A new object with the elements grouped by the key returned by the setterPropertyName function.
Example
```
const pets = [
    { type: 'dog', name: 'Fido' },
    { type: 'dog', name: 'Chacalin' },
    { type: 'cat', name: 'Mr. Brown' },
    { type: 'cat', name: 'Night' },
]
console.log(PUtilsArray.groupBy(pets, pet => pet.type))
// {
//     dog: [
//         { type: 'dog', name: 'Fido' },
//         { type: 'dog', name: 'Chacalin' },
//     ],
//     cat: [
//         { type: 'cat', name: 'Mr. Brown' },
//         { type: 'cat', name: 'Night' },
//     ],
// }
```
- Defined in putils/array.ts:366