@effect-ts/system/_src/Experimental/Stream/_internal/api/groupBy.ts

Effect-TS is a zero dependency set of libraries to write highly productive, purely functional TypeScript at scale.

// ets_tracing: off

import type * as Tp from "../../../../Collections/Immutable/Tuple/index.js"
import type * as T from "../../../../Effect/index.js"
import * as GB from "../../GroupBy/index.js"
import type * as C from "../core.js"

/**
 * More powerful version of `Stream.groupByKey`
 */
export function groupBy_<R, R1, E, E1, A, K, V>(
  self: C.Stream<R, E, A>,
  f: (a: A) => T.Effect<R1, E1, Tp.Tuple<[K, V]>>,
  buffer = 16
): GB.GroupBy<R & R1, E | E1, K, V, A> {
  return GB.make_<R & R1, E | E1, K, V, A>(self, f, buffer)
}

/**
 * More powerful version of `Stream.groupByKey`
 *
 * @ets_data_first groupBy_
 */
export function groupBy<R1, E1, A, K, V>(
  f: (a: A) => T.Effect<R1, E1, Tp.Tuple<[K, V]>>,
  buffer = 16
) {
  return <R, E>(self: C.Stream<R, E, A>) => groupBy_(self, f, buffer)
}