Function _deduplicateBy

_deduplicateBy<T, K>(
src: Iterable<T>,
keySelector: IndexedSelector<T, K>,
): Iterable<T>
Removes duplicate elements from an iterable by the key produced by keySelector.
Type Parameters
- T
  Element type produced by the source iterable.
- K
  Key type generated from each element.
Parameters
- src: Iterable<T>
  Source iterable that may contain duplicate keys.
- keySelector: IndexedSelector<T, K>
  Selector receiving each element and its index, yielding the key used for distinctness.
Returns Iterable<T>
An iterable yielding the first element encountered for each distinct key.
Throws
Error Propagates any error thrown by keySelector.
Example
```
const data = [
  { id: 1, value: "a" },
  { id: 1, value: "b" },
  { id: 2, value: "c" },
];

const deduped = [..._deduplicateBy(data, ({ id }) => id)];
// deduped === [data[0], data[2]]
```
- Defined in src/transformers/deduplicateBy.ts:29