Function distinctBy`Const`

distinctBy<T, TKey>(
selector: IndexedSelector<T, TKey>,
setFactory?: SetFactory<TKey>,
): (src: Iterable) => Iterable
Emits source elements while removing duplicates identified by the selector key.

Curried version of _distinctBy.
Type Parameters
- T
  Element type produced by the source iterable.
- TKey
  Key type returned by the selector.
Parameters
- selector: IndexedSelector<T, TKey>
  Selector producing a comparison key for each element.
- setFactory: SetFactory<TKey> = ...
  Optional factory supplying the set used to track seen keys.
Returns (src: Iterable) => Iterable
A deferred iterable yielding the first element for each unique key.
Throws
Error Rethrows any error thrown by selector or setFactory.
Example
```
const users = [
  { id: 1, name: "Ada" },
  { id: 1, name: "Ada" },
  { id: 2, name: "Grace" },
];
const unique = [..._distinctBy(users, (user) => user.id)];
console.log(unique); // [{ id: 1, name: "Ada" }, { id: 2, name: "Grace" }]
```
or using the curried version:
```
const unique = [
  ...pipeInto(
    [
      { id: 1, name: "Ada" },
      { id: 1, name: "Ada" },
      { id: 2, name: "Grace" },
    ],
    distinctBy((user) => user.id)
  ),
];
console.log(unique); // [{ id: 1, name: "Ada" }, { id: 2, name: "Grace" }]
```